The Turkish invasion of Cyprus began on 20 July 1974 and progressed in two phases over the following month. Taking place upon a background of intercommunal violence between Greek and Turkish Cypriots, and in response to a Greek junta-sponsored Cypriot coup d'état five days earlier, it led to the Turkish capture and occupation of the northern part of the island.

The coup was ordered by the military junta in Greece and staged by the Cypriot National Guard in conjunction with EOKA B. It deposed the Cypriot president Archbishop Makarios III and installed Nikos Sampson. The aim of the coup was the union (enosis) of Cyprus with Greece, and the Hellenic Republic of Cyprus to be declared.

The Turkish forces landed in Cyprus on 20 July and captured 3% of the island before a ceasefire was declared. The Greek military junta collapsed and was replaced by a civilian government. Following the breakdown of peace talks, Turkish forces enlarged their original beachhead in August 1974 resulting in the capture of approximately 36% of the island. The ceasefire line from August 1974 became the United Nations Buffer Zone in Cyprus and is commonly referred to as the Green Line.

Around 150,000 people (amounting to more than one-quarter of the total population of Cyprus, and to one-third of its Greek Cypriot population) were expelled from the northern part of the island, where Greek Cypriots had constituted 80% of the population. Over the course of the next year, roughly 60,000 Turkish Cypriots, amounting to half the Turkish Cypriot population, were displaced from the south to the north. The Turkish invasion ended in the partition of Cyprus along the UN-monitored Green Line, which still divides Cyprus, and the formation of a de facto Autonomous Turkish Cypriot Administration in the north. In 1983, the Turkish Republic of Northern Cyprus (TRNC) declared independence, although Turkey is the only country that recognises it. The international community considers the TRNC's territory as Turkish-occupied territory of the Republic of Cyprus. The occupation is viewed as illegal under international law, amounting to illegal occupation of European Union territory since Cyprus became a member.