The Serbs of Croatia (Srbi u Hrvatskoj) or Croatian Serbs (hrvatski Srbi) constitute the largest national minority in Croatia. The community is predominantly Eastern Orthodox Christian by religion, as opposed to the Croats who are Catholic.
In some regions of modern-day Croatia, mainly in southern Dalmatia, ethnic Serbs possibly have been present from the Early Middle Ages. Serbs from modern-day Serbia and Bosnia-Herzegovina started actively migrating to Croatia in several migration waves after 1538 when the Emperor Ferdinand I granted them the right to settle on the territory of the Military Frontier. In exchange for land and exemption from taxation, they had to conduct military service and participate in the protection of the Habsburg monarchy's border against the Ottoman Empire. They populated the Dalmatian Hinterland, Lika, Kordun, Banovina, Slavonia, and western Syrmia. From the beginning of the 20th century, the Croat-Serb Coalition led by Croat Frano Supilo and Serb Svetozar Pribićević governed the Kingdom of Croatia-Slavonia until the dissolution of Austria-Hungary. After the creation of the Kingdom of Serbs, Croats and Slovenes in 1918 (later renamed to Yugoslavia), a few thousand Serbs moved to Croatian territory. During World War II, Serbs were targeted for extermination as part of genocide by the Ustashas in the Nazi German puppet state Independent State of Croatia (NDH).
After the beginning of the breakup of Yugoslavia and Croatia's proclamation of independence, the Serbs living in Croatia rebelled against the Croatian government and proclaimed the Republic of Serbian Krajina (RSK) on parts of Croatian territory, which led to the Croatian War of Independence (1991–1995). Several RSK leaders have been later convicted of war crimes by the ICTY. After the Croatian Army's Operation Storm, the RSK ceased to exist, its territory was reincorporated into Croatia, and approximately 200,000 Serbs fled from the country.