My Five-year plan^{[nb 1]} in the German Wikipedia helps me keep track of (mostly Japan-related) articles I want to improve/create but can’t do so immediately because I need more time, more sources or in most cases, both. As I seem to be stuck in the Japan niche in WP anyway, these are my similar plans for the en-WP. It also contains unfinished articles and pieces.

Elections redlist

Japanese electoral districts

Interesting Districts

Most of this section is as of 2014 before the D breakdown turned into ultimate splintering. But since CD seems to collect the pieces very slowly – district by district, defector by defector – and deliberately (to keep it ideologically coherent this time beyond just being anti-L), the same map might still hold in its basic outlines one/two/three/... Rep. elections down the road/whenever this process leads to a clear new two-party consolidation [of course, only unless another major realignment comes along].

de:Benutzer:Asakura Akira/Projekt Kokkai/Übersicht Shūgiin contains a comprehensive overview of all H.R. members since 1996; since party membership/nominations/caucus membership are given only for the time of election or immediately after, not accounting for changes between elections, it does more or less the same as this in a visualized form (the party colours used are given in the intro).

Strongholds

Remaining "Democratic kingdoms"

Strictly Dems:

DPJ→DP: Miyagi 5th district (Azumi), Shizuoka 6 (Watanabe)
NFP→DPJ→DP: Aichi 2 (Aoki→Furukawa), Aichi 11 (Itō→Furumoto), Mie 2 (Nakagawa), 3 (Okada)
NFP→LP→DPJ→DP: Iwate 1 (Tasso→Shina), 3 (Sasaki→Kikawada)

Dem allies, party destroyers, friends-turned-enemies-re-turned-friends, etc.:

NFP→LP→DPJ→LF→TPJ→PLP→LP: Iwate 4 (seat of the shogunate)
NFP→DPJ→Ishin→DP: Nagano 3 (Hata→Terashima→Ide)

In rival's domain (’96) before elevation to kingdom (’00):

Fukushima 3 (Genba), Chiba 4 (Noda), Kyōto 2 (Maehara)

Kingdoms lost (’12) and regained for now (’14):

Hokkaidō 1 (Yokomichi), 8 (Hachiro→Kaneta→Ōsaka), Aichi 3 (Yoshida→Kondō)

Remaining "conservative kingdoms"

post-’09

LDP only: Aomori 3rd district (Tadamori Ōshima), Ibaraki 4th district (Kajiyama family), Gunma 4th district (Yasuo Fukuda), Gunma 5th district (Obuchi family), Chiba 11th district (Eisuke Mori), Chiba 12th district (Hamada/Nakamura), Kanagawa 2nd district (Yoshihide Suga), Kanagawa 11th district (Koizumi family), Kanagawa 15th district (Tarō Kōno), Tokyo 8th district (Nobuteru Ishihara), Tokyo 11th district (Hakubun Shimomura), Tokyo 17th district (Katsuei Hirasawa), Tokyo 25th district (Ishikawa/Inoue), Toyama 2nd district (Sumi/Miyakoshi), Ishikawa 2nd district (Yoshirō Mori), Fukui 2nd district (Makino Yamamoto), Gifu 2nd district (Yasufumi Tanahashi), Gifu 4th district (Fujii/Kaneko), Kyoto 5th district (Sadakazu Tanigaki), Tottori 1st district (Shigeru Ishiba), Shimane 1st district (Hiroyuki Hosoda), Shimane 2nd district (Takeshita family), Okayama 1st district (Ichirō Aisawa), Okayama 5th district (Murata Katō), Hiroshima 1st district (Fumio Kishida), Yamaguchi 1st district (Masahiko Kōmura), Yamaguchi 3rd district (Takeo Kawamura), Yamaguchi 4th district (Shinzō Abe), ...
NFP→LDP: Aomori 4th district (Tarō Kimura),
NFP→CP→NCP→LDP: Wakayama 3rd district (Toshihiro Nikai)
LDP→Tachinichi: Okayama 2nd district (Takeo Hiranuma)
LDP→Minna: Tochigi 3rd district (Watanabe)
LDP/PNP: Toyama 3rd district (Watanuki/Tachibana), Hiroshima 6th district (Shizuka Kamei)

Kōmei country

[But if the LDP-Kōmei alliance should ever end without a "non-aggression pact" (i.e. no competing nominations/endorsements), they'd probably need to find an agreement with the other major bloc as under Ozawa to maintain their chances in SMDs; and then again, the Sōka Gakkai turnout machine seems usually so efficient that it is not beyond imagination that it might succeed even on its own under the right circumstances...]

where NFP→Kōmeitō candidates have won all elections except the 2009 landslide : Osaka 3 (Tabata→Satō), 5 (Taniguchi→Kunishige), 6 (Fukushima→Isa), 16 (Kitagawa), Hyōgo 2 (Akaba), 8 (Fuyushiba→Nakano)
the ’03 expansion when the government turned effectively into a two-party coalition (if in fact only a few weeks later, but it was already apparent that the NCP was moving towards irrelevance as an independent force) and Kōmeitō's relative weight in the coalition increased – again, 2009 doesn't count as Kōmeitō stuck to the sinking LDP ship trusting that it would rise again soon: Tokyo 12 (Ōta), Kanagawa 6 (Ueda)
the ’12 expansion when the LDP was eager to come back and as Kōmeitō's relative weight in the coalition has increased [Forgetful LDP politicians may have been recently tempted to think the party is as dominant again as in the old days; but losing more than 10% of the district vote countrywide to a coordinated or united opposition bloc could send the LDP where? To all-time-worst territory as the 2017 Tokyo election has reminded them...]: Hokkaidō 10 (Inatsu)
lost in ’05 and contested by LDP candidates since: Okinawa 1

Where the red flag might make the difference

About 10% of the district vote – if less reliable/more variable, and probably at a higher, potentially too high "price" in terms of policy concessions given the ideological gap between the Communists and the rest – would be almost as valuable a prize as the Kōmeitō vote

The old strongholds [’96 remnants from the SNTV era, crumbled soon under the FPTP pressure towards two-party competition]: all districts in Kyoto, especially Kyoto 1–4 in and around Kyoto City, Kōchi 1 (covered initially only Kōchi City in ’96) and to a slightly lesser degree the rest of Kōchi (initially two other districts; in ’14, Communist vote in both of today's Kōchi districts stood at around 20% in L/D/C-three+-way-contests [as opposed to the L/C-contests which were widespread in ’14 as the DPJ had imploded and the "tea parties" no longer on the rise, but not ready yet to realign with the D or L camp]), (###anything else worth mentioning?###)
Districts where opposition/non-LDP-Kōmeitō candidates have only been successful when the JCP has not nominated a candidate – as it did unilaterally in about two dozen HR districts in ’05 and in roughly half the country in ’09 (ja:共産空白区), and for the first time in an explicit mutually-agreed countrywide cooperation, with even partial cross-endorsments in the ’16 HC election (ja:民共共闘)
- (###incomplete###)
- Fukuoka 5: Im most elections, L/x/C with an L winner and ~11,000~21,000 C votes; in ’09 L/D with D victory by <24,000 votes
- Nagasaki 2: In most elections, L/x/C with an L winner and ~9,000~17,000 C votes [>30,000 in an L/C/Liberal League race in ’00]; in ’09 L/D [+3 minor] with D victory by <15,000 votes
- Nagasaki 3: In most elections, L/x/C with an L winner and ~5,000~8,000 C votes [>30,000 in an L/C-two-way-race in ’14]; in ’05 L/D with L victory by <9,000 votes, in ’09 L/D with D victory by <2,000 votes
- Ōita 2: In most elections, L/S/C with an L winner and ~5,000~18,000 C votes; in ’09 L/S with S victory by <5,000 votes

Battlegrounds

H.R.

The most unreliable districts in the country (had never returned an incumbent before 2017): Osaka 10 (Ishigaki→Tsujimoto→Matsunami→Hida→Matsunami→Tsujimoto→Matsunami→Tsujimoto), Saga 1 (Haraguchi→Sakai→Haraguchi→Fukuoka→Haraguchi→Iwata→Haraguchi)
The recent chessboard/last Democratic trenchline (D ’03→L ’05→D’ 09→L ’12→D ’14): Aichi 5 (Akamatsu→Kimura→Akamatsu→Kanda→Akamatsu), 7 (Kobayashi→Suzuki→Yamao→Suzuki→Yamao)

If the country should see a truly competitive election again soon, either by the LDP falling, a third force rising [though depending on how that happens it might redraw the map through defections], the LDP-Kōmeitō alliance breaking up, space aliens arriving, the Democrats regaining appeal as a viable alternative or a combination of these factors, the more likely actual battlegrounds would probably rather be:

districts that went L ’00→D ’03→L ’05→D’ 09→L ’12, i.e. L-leaning districts flipped by the relatively strong D result in ’03 (L 168/D 105) and then went swinging wildly with the three following pro-L/anti-L/anti-D landslides (but unlike the above-mentioned not →D ’14, those were actually former D strongholds, only overturned the L landslide in ’05 and the anti-D landslide in ’12): (###TBC###)
and some of the districts that went from D or NFP in ’96 (L 169/NFP 96/D 17) to L in ’00 and were close, but stayed L in ’03 and then swung with the following three landslides: (###TBC###)

H.C.

2019 battlegrounds (激戦区, gekisen-ku) among SMCs as identified by the LDP campaign in the 2019 election before the official campaign start; a few of them turned out not to be too close; and one or two SMCs considered safe by the LDP ended up with rather tightish margins; but basically its pre-election analysis was right: it won all its 16 "safe" SMCs and lost ten of the 16 "battlegrounds", sorted by margin:

15.6 Nagano (reapportioned 2→1, pre-election: split seats; opposition win) – ed.: strong opposition incumbent
14.5 Ehime (opposition gain) – ed.: L incumbent had retired, L candidate relatively weak
11.5 Okinawa (opposition hold) – ed.: Okinawa had been consistently uphill anti-Pentagon/LDP territory for a while (anti-base governor, assembly majority, three of four H.R. members) and the only "battleground" already fully in opposition hands before the election
4.4 Akita (opposition gain)
4.1 Niigata (reapportioned 2→1, pre-election: split seats; opposition win)
3.5 Ōita (opposition gain)
2.9 Yamagata (opposition gain)
2.7 Iwate (opposition gain)
2.4 Shiga (opposition gain)
0.9 Miyagi (reapportioned 2→1 with two pre-election L incumbents due to previous party switchovers; opposition win)
6.0 Mie (L hold)
7.0 Aomori (L hold)
9.8 Yamanashi (L hold)
10.3 Tokushima-Kōchi (combined from 2 SMCs into 1; pre-election: both held by L; L win) – ed.: C candidate for the opposition
12.8 Fukushima (L hold) – ed.: strong L incumbent
23.2 Saga (L hold)

Closest 2019 result among the SMCs not classified as battlegrounds by L:

6.8 Nagasaki

Oddities

Switching sides: In Osaka 14 in the 2009 election, Takashi Nagao (DPJ) defeated incumbent Takashi Tanihata (LDP; but originally a Socialist until the 1990s); in 2012, Tanihata (Ishin) took back his seat from Nagao (LDP)
Winner of the one-district-for-the-whole-family challenge [under the current SMD electoral system only; not comparable with the cross-system century-spanning inheritance records set by Hatoyamas, Koizumis, Kishis, etc.]: Saitama 14 has been represented by father Yatarō (1996–2000), son Takashi (2000–2009) and younger son Hiromi (since 2012) from the Mitsubayashi family [also participates in the keep-the-political-family-business-running endurance contest, but not yet for medals: grandfather Kōzō was first elected to the Miyuki village assembly in 1924, the Saitama prefectural assembly in 1928, to Miyuki mayor (at that time compatible with assembly membership) in 1939 and to the House of Representatives from Saitama at-large in 1946 before being purged in 1947; Yatarō only made it to the Diet in 1967].

Unconstitutional elections

full list of Supreme Court rulings on malapportionment: ja:一票の格差#衆議院選挙及び参議院選挙における最高裁判決例

Unconstitutional or "in an unconstitutional state" elections (either way, resulting only in reapportionment, never in invalidation so far – and probably not in the future [because of the mess the country would find itself in after illegitimate Diet members have produced laws for a year or two]):

House of Representatives 1972, 1980, 1983, 1990, 2009, 2012, 2014
House of Councillors: 1992, 2010, 2013

By-elections

NDL, Reference 2005.12, pp. 76–105: Ryō Satō (佐藤令): 戦後の補欠選挙

Shūgiin districts

1890–1902: "small districts"

1902–1920: "large districts"

1920–1928: "small districts"

1928–1946: "medium districts"

1946–1947: "large districts"

1947–1996: "medium districts"


										Hokkaido 1 2 3 4 5
									Aomori 1 2
									Akita 1 2	Iwate 1 2
								Niigata 1 2 3 4	Yamagata 1 2	Miyagi 1 2
							Ishikawa 1 2	Toyama 1 2	Tochigi 1 2	Fukushima 1 2 3
						Fukui At-large	Nagano 1 2 3 4	Gunma 1 2 3	Saitama 1 2 3 4 5	Ibaraki 1 2 3
		Shimane At-large	Tottori At-large	Hyogo 1 2 3 4 5	Kyoto 1 2	Shiga At-large	Gifu 1 2	Yamanashi At-large	Tokyo 1 2 3 4 5 6 7 8 9 10 11	Chiba 1 2 3 4
		Yamaguchi 1 2	Hiroshima 1 2 3	Okayama 1 2	Osaka 1 2 3 4 5 6 7	Nara At-large	Aichi 1 2 3 4 5 6	Shizuoka 1 2 3	Kanagawa 1 2 3 4 5
Saga At-large	Fukuoka 1 2 3 4					Wakayama At-large	Mie 1 2
Nagasaki 1 2	Kumamoto 1 2	Oita 1 2		Ehime 1 2 3	Kagawa 1 2
	Kagoshima 1 2 3	Miyazaki 1 2		Kochi At-large	Tokushima At-large
Amami (SMD)
Okinawa (from 1970) At-large

1996–: "small districts"

List of Districts of the House of Representatives of Japan


PR blocks: Hokkaidō Tōhoku Northern Kantō Tōkyō Southern Kantō Hokuriku-Shin'etsu Tōkai Kinki Chūgoku Shikoku Kyūshū Defunct: (district abolished in the 2002 redistricting and reapportionment) {eliminated in the 2013 redistricting/reapportionment} [eliminated in the 2017 redistricting/reapportionment] as soon as 2020 census figures are available: Adams method for apportioning HR majoritarian seats to prefectures										Hokkaido 1 2 3 4 5 6 7 8 9 10 11 12 (13)
									Aomori 1 2 3 [4]
									Akita 1 2 3	Iwate 1 2 3 [4]
								Niigata 1 2 3 4 5 6	Yamagata 1 2 3 (4)	Miyagi 1 2 3 4 5 6
							Ishikawa 1 2 3	Toyama 1 2 3	Tochigi 1 2 3 4 5	Fukushima 1 2 3 4 5
						Fukui 1 2 {3}	Nagano 1 2 3 4 5	Gunma 1 2 3 4 5	Saitama 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15	Ibaraki 1 2 3 4 5 6 7
		Shimane 1 2 (3)	Tottori 1 2	Hyogo 1 2 3 4 5 6 7 8 9 10 11 12	Kyoto 1 2 3 4 5 6	Shiga 1 2 3 4	Gifu 1 2 3 4 5	Yamanashi 1 2 {3}	Tokyo 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25	Chiba 1 2 3 4 5 6 7 8 9 10 11 12 13
		Yamaguchi 1 2 3 4	Hiroshima 1 2 3 4 5 6 7	Okayama 1 2 3 4 5	Osaka 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19	Nara 1 2 3 [4]	Aichi 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15	Shizuoka 1 2 3 4 5 6 7 8 (9)	Kanagawa 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Saga 1 2 {3}	Fukuoka 1 2 3 4 5 6 7 8 9 10 11					Wakayama 1 2 3	Mie 1 2 3 4 [5]
Nagasaki 1 2 3 4	Kumamoto 1 2 3 4 [5]	Oita 1 2 3 (4)		Ehime 1 2 3 4	Kagawa 1 2 3
	Kagoshima 1 2 3 4 [5]	Miyazaki 1 2 3		Kochi 1 2 {3}	Tokushima 1 2 {3}
Okinawa 1 2 3 4

Sangiin districts since 1947

List of districts of the House of Councillors of Japan

Number represents district magnitude, i.e. members elected in one regular election. (in parentheses): Election in which a reapportionment first applied. Note that it takes another regular election until the change is effective in both classes.


As of 2019: 32 seats from 32 single-member districts [where SNTV=FPTP/winner-take-all; swing and therefore usually decide* an election] 8 seats from 4 two-member districts [where SNTV boils down to: very hard to win both, very hard to lose both unless one side is unassailably dominant (well over two-thirds) or the other side fails to nominate realistically; usually irrelevant* for the outcome] (Dems tried a 2+-district strategy in 2010 – an all-out failure; #### (201x) has argued it was successful in helping to turn out PR voters; but of what use is that if you lose your governing majority?) 34 seats from nine 3+-member districts [where SNTV = impossible to win all seats, unlikely to lose all seats, usually less relevant* for the outcome, and a reasonable chance for smaller parties to gain a majoritarian seat] (Hashimoto's 1998 disaster being the notable exception; 2013 (Dem/Kan nomination blunder in Tokyo etc.) also illustrated how they can make the difference between a defeat and a wipe-out) 50 seats from 1 proportional district [important for small parties or for a 2/3-majority, but otherwise not very relevant* for the outcome] (but comparatively more than in the HR) * refers to the balance of power, i.e. the question if a ruling party or coalition wins/holds/loses a majority – of course, to the voters and the affected parties it matters whether a Communist or a Democrat wins the second seat in Kyōto, and it might even matter for the balance of power if maybe in a few centuries the Democrats govern again. But until such time, it doesn't.										Hokkaido 4→2 (1995)→3 (2016)
									Aomori 1
									Akita 1	Iwate 1
								Niigata 2→1 (2016)	Yamagata 1	Miyagi 1→2 (1995)→1 (2016)
							Ishikawa 1	Toyama 1	Tochigi 2→1 (2007)	Fukushima 2→1 (2013)
						Fukui 1	Nagano 2→1 (2016)	Gunma 2→1 (2007)	Saitama 2→3 (1995)→4 (2019)	Ibaraki 2
		Tottori-Shimane formerly Shimane and Tottori 2×1→1 (2016)		Hyogo 3→2 (1995)→3 (2016)	Kyoto 2	Shiga 1	Gifu 1→2 (1995)→1 (2013)	Yamanashi 1	Tokyo 4→5 (2007)→6 (2016)	Chiba 2→3 (2007)
		Yamaguchi 1	Hiroshima 2	Okayama 2→1 (2001)	Osaka 3→4 (2013)	Nara 1	Aichi 3→4 (2016)	Shizuoka 2	Kanagawa 2→3 (1995)→4 (2016)
Saga 1	Fukuoka 3→2 (1995)→3 (2016)					Wakayama 1	Mie 1
Nagasaki 1	Kumamoto 2→1 (2001)	Oita 1		Ehime 1	Kagawa 1	National [from 1983: proportional] district 50→48 (2001)→50 (2019) (unlike HR, dual candidacy in a local district and the PR district not allowed)
	Kagoshima 2→1 (2001)	Miyazaki 1		Tokushima-Kōchi formerly Kochi and Tokushima 2×1→1 (2016)
Okinawa (from 1970) 1

On H.C. 1- vs. 2+-member districts

Note that in the House of Councillors where both single- and multi-member districts are used in parallel in the majoritarian SNTV tier, the variation in district magnitude may have a significant impact on the actual electoral influence of the district independent from the quantitative vote weight in terms of voters per member, especially between single- and multi-member districts: In a single-member district, the winner takes the only seat (=all), the second-placed candidate gets nothing; winning it may be "expensive" in terms of votes and campaign effort because it may take a high vote share to win it, but also highly "profitable" for the winning party in the overall result because winning it denies all competitors a seat in the district. In a two-member district, the winner gets one seat (=half of the seats available), and the second-placed candidate gets one (=the other half), regardless of how high the difference in votes/vote share is between the two, only the third- and lower-placed candidates lose. Winning a single seat in a multi-member district is "cheaper" because it may be won with a much lower vote share, but with less influence on the total result; winning all seats and thus denying competitors any seats would be much more "expensive". This gives single-member districts potentially more impact and often more media and campaign attention in House of Councillors elections because they may flip (completely) by only a relatively small swing in votes whereas it would take huge vote swings to flip all seats (and not only the top seat) in a multi-member district.

Quantitatively, this effect is described by the threshold of exclusion and the threshold of inclusion, i.e. the highest vote share with which it is possible [under the most unvaforable distribution of votes] not to win a seat and the lowest vote share with which it is possible [under the most favorable distribution of votes] to win a seat. The latter quickly approaches zero under SNTV for a high number of candidates and/or at high magnitudes; but in Japan, there is a hard legal election threshold which is higher, yet still low enough to be rarely relevant: In the House of Councillors, the legal quorum (法定得票, hōtei tokuhyō) is valid votes÷6÷district magnitude; if a candidate is placed among the winning candidates in terms of ranking but has received less votes, he is not elected, and a repeat election (再選挙, sai-senyko) must be held.

Note for политрукs and other crusaders

^ no serious political connotations intended

Appendix C: Party colours

Just a sandbox, not sure if it becomes a proposal for WP (and if yes, for which one); but I find the status quo quite unsatisfactory – using practically the same colour for three different contemporary rival parties may satisfy a sense of order, but is not very helpful to readers.

General principle: Mirror continuities in the colour scheme, either by using the same colour or variations thereof for successor/precursor parties and related, but discernible colours for ideologically or strategically aligned parties

Based on: 1. Originally on the 1890–today pie charts on Commons for H.R. elections and H.C. elections (as far as I have seen all by Commons:User:Monaneko) which already followed the aforementioned principle, 2. Minimally modified in de:Benutzer:Asakura Akira/Projekt Kokkai#Parteien and 3. developed into two colour schemes for text background in the de.wp workpages List of H.R. members since 1996 and List of H.C. members since 1947 (so far only Northern and Eastern Japan), now 4. streamlined a bit further ###[@AA: A more radical approach to 4. would be to leave the strategy, "group flow" and personal part (which undoubtedly plays a huge role as "Sengoku-period"-patterns of leadership and fealty, treachery, rebellion, alliances, etc. are still one lens through which one can understand some things in Nagatachō) out completely and create groups exclusively on policy/ideology – then one could see continuity from the NFP (big tent; but platform & leadership were rather right/right) to the 3rd pillar (and some of Ozawa's former followers indeed ended up there instead of following his strategic shift from L reformer to rebel, but still potential L ally to now S ally with C electoral alliance and his policy shift from right/right to left/left [or inversely in a theory of political relativity view, the shift of Japan's "centre" towards the right on both main axes which he helped to initiate but did not not continue himself]). The current mixture of both aspects is probably better to organize; but a policy-only approach might be worth considering for a minute (?).]###

Party group	single colour variant	Party	Years	colour	Notes
R (Early constitutional Meiji pro-government/oligarchy parties; R as in ritō, ruling party or reactionary)		Taiseikai	1890–1891
		Chūō Kōshōkai "Central negotiation group"	1892–1893		Not in direct continuity, and not actually a party, but a caucus formed after the 2nd H.R. election; but supportive of the cabinet, and therefore in support of oligarchic rule (if for a different oligarch)
		Kokumin Kyōkai "Popular Society"	1892–1899		Formed by members of the Chūō Kōshōkai, in its time the largest ritō
		Teikokutō "Imperial Party"	1899–1905		Successor to the above; but with the formation of the Seiyūkai in 1900, the latter, as an alliance of oligarchs and conservative liberals much more likely to maintain majority control in the lower house, assumed the role of main pro-cabinet party=ultimate failure of ritō-supported government→end continuity (though the failure was already obvious by the 1st H.R. election result and the 1891 budget negotiations)
R allies		Second lane: Work ahead###
R allies
L (Liberal^{19th cent.}/Conservative^{20th cent.} mainstream L as in Liberal Party)		[Const.] Liberal Party [Rikken] Jiyūtō	1890–1898
		Constitutional Party Kenseitō	1898–1900
		(Const.) Association of political friends (Rikken) Seiyūkai	1900–1942
L allies
P (Liberal^{19th cent.}/Conservative^{20th cent.} anti-mainstream; P as in Progressive Party)		(Const.) Progressive/Reform Party (Rikken) Kaishintō	1882–1896
		Progressive Party Shinpotō	1896–1898
		True Constitutional Party Kenseihontō	1898–1910
		(Const.) Popular Party (Rikken) Kokumintō	1910–1922	(remove from P???)
L&P→D transition group	–	(Rikken) Dōshikai (Const.) Association of kindred spirits	1913–1916	(orig. commons colour; make more reddish as P breakaway?!? or put into P??)
		Seiyūhontō True Seiyū party/party of political friends	1924–1927		This defection from the Seiyūkai transformed the two commoner/bourgeois/liberal/conservative party groups ultimately into two large, truly competitive blocs; the P continuity is broken in this period for this reason [and because of the "three constitutional parties alliance" and because the Minseitō ended up as wartime "progressive"/militarist-state-capitalist [or alternatively: plain opportunist-populist], while the majority of Seiyūkai stayed more "orthodox"/constitutionalist-market-liberal for a while]
		Kenseikai Constitutional Association	1916–1927	(put into P???)
D (Shōwa anti-mainstream D as in Democratic Party)		[Const.] Democratic Party [Rikken] Minseitō	1927–1940
S ("proletarian" parties as they were called; S as in Socialists)		dozens of mini-parties	before 1932
		Shakai Taishūtō Socialist Mass Party	1932–1942
Period of widespread ideological excrement accumulation in skull interiors					obviously, the following are not exact continuities, most obviously Hatoyama was from the Seiyūkai; but the re-formation of parties is easier to understand from the beginning in 1945; and there, the majority of the Liberal Party were ex-Seiyūkai, the majority of the other major conservative party that would become eventually part of the Democratic Party when Hatoyama broke with L were ex-Minseitō politicians
L (Con. mainstream & unified conervatives L as in Liberal Party)		Nihon Jiyūtō Japanese Liberal Party
		Minshujiyūtō Democratic Liberal Party
		Jiyūtō Liberal Party (’53: "Yoshida Liberal Party")
		Jiyūminshutō Liberal Democratic Party
D (Con. anti-mainstream D as in Democratic Party)		Nihon Shinpotō Japanese Progressive Party
		Minshutō Democratic Party
		Kokumin Minshutō Popular Democratic Party
		Kaishintō Reform/Progressive Party
		Nihon Minshutō Japanese Democratic Party
L/D various other occupation era conservative/proto-LDP parties	–	Nihon Jiyūtō Japanese Liberal Party (’53 "Hatoyama Liberal Party")	1953–1954		But after the election, Hatoyama returned to his first Liberal Party for a while, while some of his followers maintained his second Liberal Party
		Kokumin Kyōdōtō Popular Cooperativist Party
		Work ahead###
S


C		Nihon Kyōsantō Japanese Communist Party	1945–
Road ends ahead###
S/C various (occupation era leftist splinters)
"centre/centre-right" in the 1955 system:
DSP-K bloc
NLC-SDF bloc
other L&S splinters
1990s: New party boom
O Ozawa's parties except L/D		"New Frontier Party (NFP)" Shinshintō New Progressive Party
		Jiyūtō Liberal Party (LP)
		"Kizuna Party" Shintō Kizuna ~ New Kizuna/unity/bondedness Party (cf. wikt:絆 [usually spells きずな, not きづな], wikt:ja:きずな, post-2011 Tōhoku reconstruction effort, kanji of the year]</ref>	2011–2012		not strictly an Ozawa party; but formed by Ozawa "children", in a joint caucus with Ozawa's party when he left D, and merged into Ozawa's party before the election
		Kokumin no Seikatsu ga Daiichi (Seikatsu) People's life/livelihoods first
		"Tomorrow Party of Japan (TPJ)" Nihon Mirai no Tō Japanese Future Party
		"People's Life Party [& Taro Yamamoto & friends] (PLP)" Seikatsu no Tō [& Yamamoto Tarō & nakamatachi] (Seikatsu) Party of Life/Livelihoods [& member register]	2012–2019
		Jiyūtō Liberal Party (LP)	2012–2019
		"Democratic Party for the People" Kokumin Minshutō People's/Popular Democratic Party	2018–		Ozawa himself, although now a member, is probably no longer relevant here, not in the classical sense of a "Don/shogun" anyway; but the party model is still comparable to some of Ozawa's earlier parties (before he ended up in alliance with S and even C): Basically mainstream-LDP-voter-compatible policies with an anti-LDP label [& remembering ~~the brief period of revolving-door D governments~~, excuse me, the long three years with only eight D cabinet lineups: old-school-LDP politics]
D as (initially) new anti-mainstream		"Democratic Party of Japan (DPJ)" Minshutō Democratic Party	1996–1998
		"Democratic Party of Japan (DPJ)" Minshutō Democratic Party	1998–2016
		"Democratic Party (DP)" Minshintō Dem[ocratic] Progressive Party	2016–2018
		Various splinter remnants, mainly Group of Independents
Various L/D splinters since 1990s:
L allies & close enemies (i.e. initially hostile, later boomeranging defections)	...
D allies & close enemies	...
L→D switchers	...
D→L switchers	...
CD		"Constitutional Democratic Party of Japan" Rikken Minshutō Constitutional Democratic Party	2017–
late 2000s/early (?) 2010s: "Tea parties/3rd pillar": Watanabe-Hashimoto-.../"neocon"/"neoliberal" branch	–	Kaikaku Club→Shintō Kaikaku	2008/10–2016
		"Your Party (YP)" Minna no Tō (Minna) Party for everyone/Everyone's party	2009–2014
		"Unity Party (UP)" Yui no Tō (Yui) ~Party of Yui/cohesion/togetherness/mutual cooperation (cf. wikt:結, wikt:ja:ゆい, premodern village culture/rice cultivation in Japan, post-2011 Tōhoku reconstruction effort, ..., in that vein, "unity" is fine)	2013–2014
		various ex-Minna splinters (Genki, MuKu, ...) & proto-Koike groups (ToFi, NiFi)	2014–2016 2016/17	(use Minna colour? any conflicts???)
		Kibō no Tō (Kibō) Party of Hope	2017–
		"Japan Restoration Party (JRP)" Nippon Ishin no Kai (Ishin) Japanese Reformation/Restoration Association	2012–2014
		"Japan Innovation Party (JIP)" Ishin no Tō (Ishin) Party of Reformation/Restoration	2014–2015/6
		"Initiatives from Osaka (IO, IfO, etc.)" Ōsaka Ishin no Kai (Ishin) Osaka Reformation/Restoration Association	2015–2016		Using the same colour works fine. Why? Because there were no major elections in the brief period of coexistence ’15–’16, and at least in the lower house of the Diet, the rump Ishin no Tō already formed a joint caucus with D Using the same colour is sensible. Why? Because all these parties are Ishin parties by name, and Hashimoto parties by [if only briefly formal] leadership, and all are more or less hard-right/hard-right in a 2D-economy/constitution political compass like most of the other "3rd pillar/tea parties", though some including the Ishin no Tō were more moderate/D-compatible on the constitution axis
		Nippon Ishin no Kai (Ishin) Japanese Reformation/Restoration Association	2016–
3rd pillar: Hiranuma-Ishihara/"retrocon"/"neostatist" branch		Kokueki to kokumin no seikatsu o mamoru kai ~As. for protecting the national interest and people's livelihoods more commonly known as Hiranuma group	2009–2010/11		(after Hiranuma's departure, the "Hiranuma group" as a caucus continued to exist for a year, but there should be no conflicts)
		Tachiagare Nippon →Taiyō no Tō	2010–2012
		Jisedai no Tō →Nippon no kokoro o taisetsu ni suru tō →Nippon no kokoro	2014–2018
Road ends ahead###

Basic intro-rewrite Provinces of Japan (WIP)

Not convinced yet if I really want to do this here. I usually don't feel sufficiently comfortable messing much with pre-bakumatsu history, but at least the first-approach basics shouldn't be portrayed in such a way that the Roman province of Britannia suddenly pops up in Modern times to be "renamed" by the Roman Emperor.

Provinces of Japan (令制国, Ryōsei-koku, "ryō system provinces"; ryō is the adminstrative part of Ritsuryō) were contiguous administrative divisions of Japan under the Imperial Court in antiquity (6th/7th–12th century) and after that, while never formally abolished, decayed into purely geographical units by the late 19th century. As such, they remain in occasional use.

During the Japanese Middle Ages (12th–15th/16th century), they were gradually replaced with a feudal hierarchy that initially started out based on the provincial division in the form of provincial military governors appointed by the shōgun (shugo), to become essentially irrelevant by the civil wars of the 16th century (Sengoku period) as the centrally or lower-level appointed administrators had evolved into practically independent or sub-vassalized feudal rulers. However, as the primary ceremonial, statistical (e.g. for kokudaka land surveys) and geographic territorial division of Japan, provinces continued to be used into the Meiji Restoration in the 19th century when the last ceremonial ritsuryō functions, titles and positions were initially briefly nominally restored and then ultimately abolished. As primary geographic frame of reference, they are mostly replaced by prefectures as well by the early- to mid-20th century. But occasionally, they are used as geographic terms even today; for example, in 2019, Sasayama City in the modern prefecture of Hyōgo, but in the Ritsuryō province of Tamba, was renamed to Tamba-Sasayama after a referendum.

Under the original ritsuryō in antiquity (and as a geographic/ceremonial division beyond), each province was divided into districts (郡, kōri/modern reading gun), further subdivided into various village-level divisions that were changed several times over the centuries (里/郷, sato/郷, gō/里, ri/村, mura, these terms are still part of many geographic names today, -mura are even a modern administrative division). As a larger top-level division, provinces were grouped into seven circuits (-dō) and one capital region (Kinai). Provincial borders often changed until the end of the Nara period (710 to 794), but remained mostly unchanged in the Middle and Early Modern Ages; but although they were no longer the relevant administrative division of the country, some smaller adjustments were made even then, for example, the early Tokugawa shogunate shifted the rivers and the provincial border between Shimousa (Lower [F]usa) and Musashi eastwards to protect their shogunate capital Edo (in the ritsuryō Toshima District of Musashi) from floods and military threats.

In the Meiji Restoration, the former feudal holdings of the shogunate and shogunate cities were replaced with prefectures while the other feudal domains (han) were formalized in the fu/han/ken (urban prefectures/feudal domains/rural prefectures) system from 1868 to 1871. Provinces do not enter into it in real-world Japan until the 1871–72 First Wave of Prefectural Mergers that followed the 1871 Abolition of -han/feudal domains and establishment of -ken/rural prefectures (haihan chiken) when the resulting, now countrywide prefectures were merged and rearranged from the Edo period feudal maze of numerous enclaves, exclaves, and tiny teritories to become contiguous, compact territories, similar to antiquity's provinces in many places.

Also in the Meiji Restoration, Hokkaidō on the island of Ezo was added to antiquity's 5 capital area provinces/7 circuits (5-ki-7-dō) system as the eighth circuit with eleven new provinces – at the time of the ancient provincial division, Ezo had not been part of the Empire. In the Northern part of Honshū that had been a gradually northwards-shifting military frontier area of the ancient Empire against the indigenous population, the now giant provinces of Dewa/Ushū and Mutsu/Rikuō/Ōshū were formally split up into Uzen (U[shū] anterior)/Ugo (U[shū] posterior) and Rikuzen (Riku anterior)/Rikuchū (Riku central)/a new smaller Mutsu. Since then, the [Hokkai]dō took increasingly the functions of a prefecture (otherwise fu/ken), and was fully recognized as a prefecture (then dō/fu/ken, to/dō/fu/ken from 1947) under law in 1946.

Reanimate the sengoku jidai (period of peaceful countries/static borders/nothing happening) with a timeline gallery from the commons

Having only a single map at one point in time for a period of perpetual conquests, intrigue and succession squabbles – basically a century-spanning game of swords [not thrones, there is only one of those, control over the country generally implies some degree of control over that throne's court in all ages after antiquity] –, leaves me as a reader with a sorely dry throat. These maps may not be the ideal ultimate illustration, but they seem a substantial improvement on the war that was never shown to the reader.

Approximate major sengoku daimyō holdings, including lower vassals, around 1520 (colours) on a map of provinces (borders): In the West, Hosokawa (blue), Amago (red) and Ōuchi (lavender/pale violet) are still powerful; in the East, Uesugi (dark blue), Hōjō (green), Takeda (brown) and Imagawa (dark violet) are among the major powers
Major sengoku daimyō around 1550: In the ancient capital region, the Miyoshi (lavender/pale violet) have taken the place of the Hosokawa, in the far West, the Amago have expanded their territory, but the Mōri (yellow) are beginning to gain ground, and the Shimazu (blue) in Kyūshū are starting to expand; in the East, the Hōjō have taken control of Musashi from the Uesugi and expanded further
Major sengoku daimyō around 1560: In modern-day Chūgoku, the Mōri are becoming dominant, while only the Amago still hold their ground; in the East, the Takeda have taken over Shinano, the Nagao (blue) have expanded from Echigo; in Owari in the centre, Oda (red) shows up as a major force to come
Major sengoku daimyō around 1570: In the West, the Mōri have defeated the Amago, Ōtomo (dark violet) and Shimazu control much of Kyūshū; Oda has brought much of the centre under his control; in the East, Tokugawa (blue) has replaced Imagawa while the Takeda have expanded into Suruga
Major sengoku daimyō around 1575, nearing the first climax as Oda rises
Major sengoku daimyō around 1580: Oda near the height of power, only briefly before his fall
Major sengoku daimyō around 1585: Toyotomi (still given on the map as Hashiba, red) has taken over Oda's position and forced the Mōri and Chōsokabe into submission, the Tokugawa gain ground in the East where the Takeda had been vanquished by Oda; Shimazu and Ōtomo control practically all of Kyūshū, and in the Northeast, Uesugi, Hōjō and Date are the remaining major belligerents
Major sengoku daimyō around 1589: Before the last turn, Toyotomi seems to face the last remaining rivals: the Tokugawa and the Southern daimyō are effectively submitted to Toyotomi, only the Hōjō (and Date) stand in his way in the East to be defeated soon; the unification appears complete.
Decision at Sekigahara 1600: After Toyotomi's death and an unresolved succession, mainly Eastern, pro- (blue) and mainly Western, anti-Tokugawa (red) forces fight the decisive battle for control, the Tokugawa victory ushers in two and a half centuries of relative peace for the country under a Tokugawa shogunate; in the coming decades, former enemies are punished (or sometimes shown leniency) and allies are rewarded (or sometimes not) as the early Tokugawa redistribute large swaths of territory between the now submitted other families and their own domain

[1] serious political connotations intended

[nb 1]