A quick one, before I temporarily delve into more general subjects instead of chronicling more events. Expect a map reflecting the administrative changes in the near future.
8. The 1900 administrative reorganisation
The 1896 annexation of Switzerland and its rapid fast-track towards a full, self-governing Imperial Circle - a Swiss condition for accession to the Empire - reinvigorated calls for increased autonomy and/or representation in several territories across the Empire.
For a quarter of a century, Hungary had been an Imperial Circle in its own right, but only in name - they were still represented on the Imperial Council by the Austrian monarch. Representatives of the Hungarian government were allowed participation in the deliberations, but the country remained a non-voting member, despite its large population and being part of the Empire since its inception. Meanwhile, the non-Magyars of Transylvania, Banat/Vojvodina, Croatia and Upper Hungary were subjected to Magyarisation policies, despite the 1883 enactment of a Nationalities Law, which enshrined minority rights. Hungary's ethnic minorities looked towards Austria as a more reliable protector of their cultural and linguistic rights. But even there, local minorities (Czechs, Slovenes, Italians) had their own set of grievances and were pushing increasingly hard for more autonomy within Austria.
The nationalities question became urgent enough for the states of the German Empire to negotiate a set of reforms. After long, protracted discussions, Germany's constituent states concluded the 1900 Munich Accords, promulgating the following administrative reforms:
- The Hungarian Circle would henceforth carry a sovereign vote on the Imperial Council, independent of Austria. As head of government, the Prime Minister of Hungary would be the official representative, while the office of head of state remained (albeit ceremonially) with the Austrian monarch.
- Transylvania (Siebenbürgen) would be reinstated as a Principality under the Austrian crown, except for the Magyar-inhabited Seklerland, which would become an independent province within the Hungarian Circle.
- Upper Hungary  would remain part of Hungary, but form an autonomous region with its own parliament.
- The Vojvodina and Banat regions would be divided between Hungary and Austria. Majority-Magyar areas would be merged into Hungary proper, while the remaining territory  would join Austria as the autonomous Banat Province. Hungary would retain influence in Transylvania and the Banat by having the right to appoint a vice-governor. A quarter of the seats in the Transylvanian regional assembly would be reserved to represent Hungarian interests.
- Hungarian-ruled Croatia-Slavonia and the Austrian crown land of Dalmatia would be merged into the unitary and unencircled Kingdom of Croatia (which previously existed between 1848-1871). It received privileges just short of full independence. The title of King would remain with the House of Habsburg, and the Imperial constitution remained binding (except for specific exemptions to accomodate their form of autonomy), but otherwise Croatia would be almost completely self-governing.
- In Austria, Bohemia and Moravia would receive a joint Czech parliament, albeit with limited powers.
- Istria and the County of Görz/Gorizia were merged into the Duchy of Carniola (Krain), which was elevated to a Grand Duchy and granted its own parliamant. Trieste remained a Free City and a separate entity within the Austrian Circle.
- The electoral system was reformed to better account for regional interests. The Imperial Circles would lose their purpose as electoral constituencies for the Bundestag (Imperial Diet). Instead, this function was shifted towards the Circles' first-level subdivisions. Each constituency would be represented proportionally according to their population, with the number of representatives determined every ten years according to the official imperial census. The Dutch  and Hungarian  Circles (mostly) retained their provinces and counties as their principal subdivisions for internal government, but introduced higher-level territorial entities without further administrative powers.
- The Imperial Council would keep the final say on foreign affairs, defence and other "grave matters of state", but vote weighing was adjusted as follows (former weight in brackets):
Prussia: 3 (2)
Austria: 3 (2)
Netherlands: 1 (1)
Denmark: 1 (1)
Bavaria: 1 (1)
Saxony: 1 (1)
Hungary: 1 (-)
Switzerland: 1 (-) (from 1907)
This ensured that the great powers Prussia and Austria would keep half of the votes within the Imperial Council, however at the cost of Dutch, Danish, Bavarian and Saxon influence. In the face of the urgent nationalities question, the smaller powers agreed with this temporary distribution, subject to renegotiation after five years. But the Imperial Council started being fundamentally questioned as an institution as well. It increasingly became viewed as an anachronistic, aristocratic institution, or impractical now that no less than eight Circles were represented. The continuing hegemony of Prussia and Austria also drew more and more protestations.
Footnotes: Although it never was a very well-defined area, here it comprises most of what is OTL's Slovakia and the Ukrainian Zakarpattia Oblast. The southern border follows the Hungarian counties of Nyitra (Neutra), Komarom (Komarn), Esztergom (Gran), Hont and Nógrád (Neuburg) north of the Danube; Gömör-Kishont (Gemer-Kleinhont), Abaúj-Torna (Abau-Tornau), Zémplen (Semplin), Ung, Bereg (Berg); Ugocsa (Ugotsch) north of the Tisza/Theiß river; and Máramaros (Maramuresch).
 Mostly inhabited by Romanians, Germans, Serbs and Croatians.
 The provinces of the Netherlands and other territories encircled by it were merged to form the following "gewesten":
- Holland: North Holland, South Holland, Utrecht, Zealand;
- Brabant: North Brabant, South Brabant, Antwerpen;
- Gelderland-Overijssel (Gelderland-Oberissel): Gelderland, Overijssel, Bentheim-Lingen;
- Groningen: Groningen, Drenthe, East Frisia;
- Flanders (Flandern): East Flanders, West Flanders, Artois/Artesien; - Wallonia (Wallonien): Liège/Lüttich, Namur/Namen, Hainaut/Hennegau;
- The status of Limburg, Frisia, and the Grand Duchy of Luxemburg remained unchanged.
 Hungary proper was divided into East and West provinces, roughly along the Donau river. On the West side, the border follows the counties of Komarom (Komarn; south of the Danube), Fejér (Weißenburg), Tolna (Tolnau) and Baranya (Branau). The all-Hungarian capital Budapest fell entirely within East Hungary. The remaining entities within the Hungarian Circle were Upper Hungary, Seklerland and the Free City of Fiume/Pflaum.