At the end of November 1920, the Yugoslav Sokol met with the Czechoslovak Sokol in
Ljubljana to establish the Union of Czechoslovak and Yugoslav Sokol as a forerunner of the World Sokol Federation. At the Yugoslav Sokols'
slet in 1924, the matter of establishing a joint organization was revisited. To this end, an organizing committee was formed to prepare the new organization's statute and the first congress. Adam Zamoyski was appointed chairman of the committee. In 1925, an official Sokol federation was established in Warsaw. It operated from 1925 to 1939 and included organizations from Poland, Czechoslovakia, the
Kingdom of Serbs, Croats and Slovenes (from 1929 the
Kingdom of Yugoslavia), and Bulgaria, as well as the
Serbo-Lusatian "Sokół", the Union of Russian Sokols in Emigration, and the Slavic Sokol Union in America. Its activities were interrupted by the outbreak of
World War II. During the
communist period, the Sokol movement was prohibited in the territories of the socialist bloc countries. It continued to exist through Sokol organizations abroad, including in Western Europe, the United States, and Canada. ==Modern era==