Austria-Hungary quickly disintegrated after the war. The General Congress of Bukovina proclaimed the union of the province with Romania on 28 November 1918, and the Grand National Assembly proclaimed the union of Transylvania, Banat, Crișana and Maramureș with the kingdom on 1 December. Peace treaties with Austria, Bulgaria and Hungary delineated the new borders in 1919 and 1920, but the Soviet Union did not acknowledge the loss of Bessarabia. Romania achieved its greatest territorial extent, expanding from the pre-war . A new electoral system granted voting rights to all adult male citizens, and a series of radical agrarian reforms transformed the country into a "nation of small landowners" between 1918 and 1921. Gender equality as a principle was enacted, but women could not vote or be candidates. Calypso Botez established the National Council of Romanian Women to promote feminist ideas. Romania was a multiethnic country, with ethnic minorities making up about 30% of the population, but the new constitution declared it a unitary national state in 1923. Although minorities could establish their own schools, Romanian language, history and geography could only be taught in Romanian.