After World War I, the Croatians played a major part in the founding of the first football federation of the Kingdom of Serbs, Croats and Slovenes, later named the Football Association of Yugoslavia, and its headquarters were initially in Zagreb before they were moved to Belgrade in 1929.
At this point several other major clubs were founded - today's GNK Dinamo Zagreb, HNK Rijeka and NK Osijek, to name a few.