Transylvania the Romanian population of Transylvania gathered in Alba Iulia on 1 December 1918 to proclaim the union of Transylvania with the Kingdom of Romania. In Transylvania, there are many medieval smaller towns such as Sighișoara, Mediaș, Sebeș, and Bistrița. Official censuses with information on Transylvania's population have been conducted since the 18th century. On May 1, 1784 the Emperor Joseph II called for the first official census of the Habsburg Empire, including Transylvania. The data was published in 1787, and this census showed only the overall population (1,440,986 inhabitants). , a 19th-century Hungarian statistician, estimated in 1842 that in the
Transylvania 1526, Transylvania was a voivodeship in the Kingdom of Hungary, led by a voivode appointed by the King of Hungary. After the Battle of Mohács in 1526, Transylvania became part of the Kingdom of János Szapolyai. Later, in 1570, the kingdom transformed into the Principality of Transylvania, which was ruled primarily by Calvinist Hungarian princes. During that time, the ethnic composition of Transylvania transformed from an estimated near equal number of the ethnic groups to a Romanian majority. Vasile Lupu estimates their number already more than one-third of the population of Transylvania in a letter to the sultan around 1650.