After their settlement in the Balkans, Serbs formed several medieval kingdoms, which evolved into the Serbian Empire in the 14th century. By the 16th century, Serbian lands were conquered and occupied by the Ottomans, at times interrupted by the Habsburgs. In the early 19th century the Serbian revolution re-established the country as the region's first constitutional monarchy.the country became a kingdom (it was originally a principality) in 1882.