After arriving in Bessarabia, Bulgarians and Gagauzians founded their own towns, such as Bolhrad (1819) and Comrat, and around 64 (according to some sources) or 43 (according to other sources) villages. In 1856, after the Treaty of Paris, three counties of southern Bessarabia, Cahul, Bolgrad and Ismail, reverted to the Principality of Moldavia (the United Principalities after 1859). These included the cities of Bolgrad, Ismail and Chilia. Gaguzian settlements centred on Comrat, however, remained in the Russian Empire. A Bulgarian high school (gymnasium), the Bolhrad High School, was founded in Bolgrad (Bolhrad) on June 28, 1858 by the Moldavian authorities of Alexandru Ioan Cuza, which had a positive effect on the development of Bulgarian education and culture, and is in fact the first modern Bulgarian gymnasium.