Croatia in the first Yugoslavia

Croatia became merged with Serbia and Slovenia to form the nation of Yugoslavia in 1918. The formation of Yugoslavia began with the formation of the Yugoslav Committee, a collection of Serbs, Croats, and Slovenes whose goal was to form a single south Slavic state. In October 1918 the Croatian Parliament declared the Kingdom of Croatia, Slavonia and Dalmatia as an independent state, which, in December that same year, merged with Kingdom of Serbia and created the Kingdom of Serbs, Croats and Slovenes. The kingdom would be renamed to Yugoslavia in 1929, and ruled by Serbian Karađorđević dynasty till Second World War. After the formation of Yugoslavia, Serbia attempted to create a "Greater Serbia" by using police intimidation and vote rigging to establish a Serbian controlled Yugoslavia. From 1929-1941 Serbian controlled Yugoslavia established control over Croatia through Serbian police force brutality and assassinations of important Croatians.

The basis of Croatia and Serbia forming a union in 1918 is to be found in the complex history of the Yugoslav Committee. The Yugoslav Committee was formed by exiles living outside the Croatian homeland during World War I. The Committee was led by Frano Supilo and Ante Trumbić and included the famous Croatian sculptor Ivan Meštrović. Each repudiated the Committee within a few years of the founding of Yugoslavia. "Yugoslavs" were Serbian, Croatian and Slovene people who identified themselves with the movement toward a single South Slavic state. Exiled Yugoslavs living in North America and Britain were the primary supporters of the Yugoslav Committee. Having established offices in London and Paris as early as 1915, the Yugoslav Committee became an active lobby for the cause of a united South Slav state during World War I.

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