The concept of the Balkan Peninsula was created by the German geographer August Zeune in 1808, who mistakenly considered the Balkan Mountains the dominant mountain system of Southeast Europe spanning from the Adriatic Sea to the Black Sea. The term of Balkan Peninsula was a synonym for Rumelia (European Turkey) in the 19th century, the former provinces of the Ottoman Empire in Southeast Europe. It had a geopolitical rather than a geographical definition, further promoted during the creation of the Kingdom of Yugoslavia in the early 20th century. The definition of the Balkan Peninsula's natural borders do not coincide with the technical definition of a peninsula and hence modern geographers reject the idea of a Balkan peninsula, while scholars usually discuss the Balkans as a region. . The term has acquired a stigmatized and pejorative meaning related to the process of Balkanization, and hence the preferred alternative term used for the region is Southeast Europe.