Greater Albania is an irredentist and nationalist concept that seeks to unify the lands that many Albanians consider to form their national homeland. It is based on claims on the present-day or historical presence of Albanian populations in those areas. In addition to the existing Albania, the term incorporates claims to regions in the neighbouring states, the areas include Kosovo, the Preševo Valley of Serbia, territories in southern Montenegro, northwestern Greece (the Greek regional units of Thesprotia and Preveza, referred by Albanians as Chameria, and other territories that were part of the Vilayet of Yanina during the Ottoman Empire), and a western part of North Macedonia.