Albanians, steadily increasing in number, may have constituted a majority in Kosovo since the 19th century, although the region's historical ethnic composition is disputed. Kosovo's political boundaries do not quite coincide with the ethnic boundary by which Albanians compose an absolute majority in every municipality; for example, Serbs form a local majority in North Kosovo and two other municipalities, while there are large areas with an Albanian majority outside of Kosovo, namely in the neighbouring regions of former Yugoslavia: the north-west of North Macedonia, and in the Preševo Valley in Southern Serbia.