Seto people are their lineal descendants. In 1920, the Treaty of Tartu between the Republic of Estonia and the Russian Federation was concluded. According to the Treaty, Setomaa was linked with Estonia. The folk have divided Setomaa into twelve parts, or communities (nulk). Names for the communities have been derived either from the central village or settlement: e.g. Irboska nulk or from the peculiarity of location. Names were also based on other features: e.g. Kohopiimänulk - implying at the local tradition of making cottage cheese ( kohopiim is a sort of cottage cheese). In the autumn of 1921 Seto people were for the first time ever given surnames. Since 1944,the western part of Setomaa belongs to the Republic of Estonia and the eastern part to the Russian Federation. This kind of division is the source of the Setos' burning problems: the split-up congregations, location of properties and relatives on the other side of the state border.