Question: What dissolved the privileges in Poland of the empire where Tamar Abakelia was from, the Kingdom that acquired some Thuringian territory in 1815, and the Habsburg Monarchy?

Passages:
Born in Khoni, Imereti (then part of Kutais Governorate, Russian Empire), Tamar Abakelia graduated from Tbilisi State Academy of Arts in 1929 and taught there beginning in 1938. Among Abakelia’s works were graphic illustrations for Nikolay Tikhonov, Shota Rustaveli, "David of Sasun", Vazha-Pshavela as well as stage decorations for the Rustaveli and Marjanishvili theaters and costume designs for the films "Arsena" (1937), "Giorgi Saakadze" (1942), and "David Guramishvili" (1945). Many of her achievements were in the field of sculpture. Noted for the dynamism of composition and artistically rounded forms, Abakelia was responsible for much of the progress of Soviet Georgian sculpture. She sculptured friezes on the Museum of Marxism–Leninism in Tbilisi, depicting the various phases of socialist construction in Georgia (1936–37). Abakelia died in Tbilisi in 1953 and was buried there, at the Didube Pantheon. 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. 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 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. Gradually their privileges were under further limitations to be completely dissolved by March Constitution of Poland in 1921.