slightly larger than Delaware
The Ottoman Empire took control of Kosovo in 1389 after defeating Serbian forces. Large numbers of Turks and Albanians moved to the region, and by the end of the 19th century, Albanians had replaced Serbs as the majority ethnic group in Kosovo. Serbia reacquired control of Kosovo during the First Balkan War of 1912, and after World War II, Kosovo became an autonomous province of Serbia in the Socialist Federal Republic of Yugoslavia (SFRY). Increasing Albanian nationalism in the 1980s led to riots and calls for Kosovo's independence, but in 1989, Belgrade -- which has in turn served as the capital of Serbia and Yugoslavia -- revoked Kosovo's autonomous status. When the SFRY broke up in 1991, Kosovo Albanian leaders organized an independence referendum, and Belgrade's repressive response led to an insurgency. Kosovo remained part of Serbia, which joined with Montenegro to declare a new Federal Republic of Yugoslavia (FRY) in 1992.
In 1998, Belgrade launched a brutal counterinsurgency campaign, with some 800,000 ethnic Albanians expelled from their homes in Kosovo. After international mediation failed, a NATO military operation began in March 1999 and forced Belgrade to withdraw its forces from Kosovo. UN Security Council Resolution 1244 (1999) placed Kosovo under the temporary control of the UN Interim Administration Mission in Kosovo (UNMIK). Negotiations in 2006-07 ended without agreement between Serbia and Kosovo, though the UN issued a comprehensive report that endorsed independence. On 17 February 2008, the Kosovo Assembly declared Kosovo independent.
Serbia continues to reject Kosovo's independence, but the two countries began EU-facilitated discussions in 2013 to normalize relations, which resulted in several agreements. Additional agreements were reached in 2015 and 2023, but implementation remains incomplete. In 2022, Kosovo formally applied for membership in the EU, which is contingent on fulfillment of accession criteria, and the Council of Europe. Kosovo is also seeking UN and NATO memberships.
Kosovo-Albania: none identified
Kosovo-Montenegro: their 2015 demarcation agreement was ratified by Montenegro in December 2015 and by Kosovo in March 2018, but the actual demarcation has not been completed
Kosovo-North Macedonia: Kosovo and North Macedonia completed demarcation of their boundary in September 2008; both countries ratified the demarcation documents on October 17, 2009, after high-level consultations resolved the disputed section of border around Debelde/Tanusevci
Kosovo-Serbia: Serbia has not recognized Kosovo's independence, and Belgrade continues to claim it as its territory; the 2013 Brussels Agreement launched a process of EU-facilitated normalization between Serbia and Kosovo process, a prerequisite for their EU accession; in February and March 2023, both the two countries accepted the Agreement on the Path to Normalization and its Implementation Annex, whose implementation remains incomplete