A former country of southeast Europe bordering on the Adriatic Sea. It was formed in 1918 as the Kingdom of Serbs, Croats, and Slovenes after the collapse of the Austro-Hungarian Empire and was renamed Yugoslavia in 1929. Under the leadership of Marshal Tito, the country became a Communist-led regime after World War II. After Tito's death in 1980, economic problems and ethnic tensions grew. Communist party control ended in 1990, and four of the six constituent republics (Slovenia, Croatia, Bosnia and Herzegovina, and Macedonia) declared independence in 1991. Serbia and Montenegro, the remaining states, abandoned the name Yugoslavia in 2003 and dissolved the federation entirely in 2006.