The northern border of the peninsula is variously defined. The concept of the Balkan Peninsula was created by the German geographer August Zeune in , [ 7 ] who mistakenly considered the Balkan Mountains the dominant mountain system of Southeast Europe spanning from the Adriatic Sea to the Black Sea.
In the 19th century the term Balkan Peninsula was a synonym for Rumelia , the parts of Europe that were provinces of the Ottoman Empire at the time. It had a geopolitical rather than a geographical definition, which was further promoted during the creation of the Kingdom of Yugoslavia in the early 20th century.
The definition of the Balkan Peninsula's natural borders does not coincide with the technical definition of a peninsula; hence modern geographers reject the idea of a Balkan Peninsula, while historical scholars usually discuss the Balkans as a region. The term has acquired a stigmatized and pejorative meaning related to the process of Balkanization. The borders of the Balkans are, due to many contrasting definitions, disputed. There exists no universal agreement on the region's components.
The term sometimes includes all of Romania , Serbia and Croatia, and southern parts of Slovenia. Although they have no territory on the peninsula, Hungary and Moldova are sometimes incorporated into discussions of the Balkans region due to cultural and historical affiliations.
The Province of Trieste in northeastern Italy , although by some definitions considered part of the Balkan Peninsula, is generally excluded from the Balkans region. In both Ottoman Turkish and modern Turkish , balkan means 'chain of wooded mountains'. From classical antiquity through the Middle Ages , the Balkan Mountains were called by the local Thracian [ 14 ] name Haemus.
