 The Kingdom underwent a crucial change in 1921 to the dismay of Croatia's largest political party, the Croatian Peasant Party (Hrvatska seljačka stranka).The new constitution abolished the historical/political entities, including Croatia and Slavonia, centralizing authority in the capital of Belgrade.The Croatian Peasant Party boycotted the government of the Serbian People's Radical Party throughout the period, except for a brief interlude between 1925 and 1927, when external Italian expansionism was at hand with her allies, Albania, Hungary, Romania and Bulgaria that threatened Yugoslavia as a whole.