Contemporary Croatia, which gained independence in 1991, is the successor of the 9th century Croatian medieval principalities established in the marches of the Carolingian Empire, followed by the Kingdom of Croatia, founded in 925 by King Tomislav. Soon after the death of the last great Croatian king, Dmitar Zvonimir, Croatia entered into a personal union with Hungary, and in the 14th century, the throne belonged to the French Anjou dynasty. After the Ottoman invasions in the 16th century and the loss of large tracts of land, Croatian dignitaries elected Ferdinand Habsburg as monarch in 1527, and the country remained within the Habsburg Empire until 1918. The first half of this period was marked by constant wars with the Ottomans and Venetian encroachment upon greater and greater areas along the coast (Istria and Dalmatia), apart from the far south, where the independent Dubrovnik Republic developed free trade in the Mediterranean between 1358 and 1808. After the defeat of Venice and a short period in which southern Croatia was incorporated in Napoleon's Illyrian provinces (1809–13), all the Croatian lands were brought together within the Habsburg Monarchy, though they were still separate entities. They were united briefly in 1848, during the Croatian national revival. After the First World War, Croatia became part of the Kingdom of Yugoslavia, which was transformed after 1945 into a Communist federation, in which Croatia was one of six republics until 1991. Although recognised as an independent state by the international community on 15 January 1992, Croatia was forced to defend its independence by armed struggle until 1995, when its occupied territories were liberated. In 1992, Croatia became a member of the United Nations, in 2009, of NATO, and on 1 July 2013, of the European Union. Croatia presided over the Council of the EU in the first half of 2020.