Question: What dissolved the privileges in Poland of the empire that helped the patriots during the Revolutionary War, the Kingdom that acquired some Thuringian territory in 1815, and the Habsburg Monarchy?

Passages:
Some reordering of the Thuringian states occurred during the German Mediatisation from 1795 to 1814, and the territory was included within the Napoleonic Confederation of the Rhine organized in 1806. The 1815 Congress of Vienna confirmed these changes and the Thuringian states' inclusion in the German Confederation; the Kingdom of Prussia also acquired some Thuringian territory and administered it within the Province of Saxony. The Thuringian duchies which became part of the German Empire in 1871 during the Prussian-led unification of Germany were Saxe-Weimar-Eisenach, Saxe-Meiningen, Saxe-Altenburg, Saxe-Coburg-Gotha, Schwarzburg-Sondershausen, Schwarzburg-Rudolstadt and the two principalities of Reuss Elder Line and Reuss Younger Line. In 1920, after World War I, these small states merged into one state, called Thuringia; only Saxe-Coburg voted to join Bavaria instead. Weimar became the new capital of Thuringia. The coat of arms of this new state was simpler than they had been previously. The Russian Empire's role in the American Revolutionary War was part of a global conflict of colonial supremacy between the Thirteen Colonies and the Kingdom of Great Britain. Prior to the onset of the war, the Russian Empire had already begun exploration along North America's west coast; and, the year following the combat's conclusion, the Eurasian empire established its first colony in Alaska. Although the Russian Empire did not directly send troops or supplies to the colonies or British Empire during the war, it responded to the Declaration of Independence, played a role in international diplomacy, and contributed to the lasting legacy of the American Revolution abroad. Poland's nobility were also more numerous than those of all other European countries, constituting some 10–12% of the total population of historic Polish–Lithuanian Commonwealth also some 10–12% among ethnic Poles on ethnic Polish lands (part of Commonwealth), but up to 25% of all Poles worldwide (szlachta could dispose more of resources to travels and/or conquering), while in some poorer regions (e.g., Mazowsze, the area centred on Warsaw) nearly 30%. However, according to  szlachta comprised around 8% of the total population in 1791 (up from 6.6% in the 16th century), and no more than 16% of the Roman Catholic (mostly ethnically Polish) population. It should be noted, though, that Polish szlachta usually incorporated most local nobility from the areas that were absorbed by Poland–Lithuania (Ruthenian boyars, Livonian nobles, etc.) By contrast, the nobilities of other European countries, except for Spain, amounted to a mere 1–3%, however the era of sovereign rules of Polish nobility ended earlier than in other countries (excluding France) yet in 1795 (see: Partitions of Poland), since then their legitimation and future fate depended on legislature and procedures of Russian Empire, Kingdom of Prussia or Habsburg Monarchy. Gradually their privileges were under further limitations to be completely dissolved by March Constitution of Poland in 1921.

Supporting sentences:
The Russian Empire's role in the American Revolutionary War was part of a global conflict of colonial supremacy between the Thirteen Colonies and the Kingdom of Great Britain. Gradually their privileges were under further limitations to be completely dissolved by March Constitution of Poland in 1921.