The Istrian–Dalmatian exodus (Italian: esodo giuliano dalmata; Slovene: istrsko-dalmatinski eksodus; Croatian: istarsko-dalmatinski egzodus) was the post-World War II exodus and departure of local ethnic Italians (Istrian Italians and Dalmatian Italians) as well as ethnic Slovenes and Croats from Yugoslavia. The emigrants, who had lived in the now Yugoslav territories of the Julian March (Karst Region and Istria), Kvarner and Dalmatia, largely went to Italy, but some joined the Italian diaspora in the Americas, Australia and South Africa. These regions were ethnically mixed, with long-established historic Croatian, Italian, and Slovene communities. After World War I, the Kingdom of Italy annexed Istria, Kvarner, the Julian March and parts of Dalmatia including the city of Zadar. At the end of World War II, under the Allies' Treaty of Peace with Italy, the former Italian territories in Istria, Kvarner, the Julian March and Dalmatia were assigned to now Communist-helmed Federal Yugoslavia, except for the Province of Trieste. The former territories absorbed into Yugoslavia are part of present-day Croatia and Slovenia.
The treaty provided the right of option of nationality to people on both sides, who might have been required to emigrate from the territory if they opted to keep their nationality by jus sanguinis (right of blood). According to various sources, the exodus is estimated to have amounted to between 200,000 and 350,000 Italians (the others being ethnic Slovenes and Croats who chose to maintain Italian citizenship) leaving the areas in the aftermath of the conflict. The exodus started in 1943 under Nazi Germany and ended completely only in 1954. According to the census organized in Croatia in 2001 and that organized in Slovenia in 2002, the Italians who remained in the former Yugoslavia amounted to 21,894 people (2,258 in Slovenia and 19,636 in Croatia).