Other significant parties formed in the era was the Serb People 's Independent Party , which later formed the Croat @-@ Serb Coalition with the Party of Rights and other Croat and Serb parties . The Coalition ruled Croatia between 1903 and 1918 . The leaders of the Coalition was Frano Supilo and Svetozar Pribićević . The Croatian Peasant Party ( HSS ) , established in 1904 and led by Stjepan Radić , advocated Croatian autonomy but achieved only moderate gains by 1918 . In Dalmatia , the two major parties was the People 's Party – a branch of the People 's Party active in Croatia @-@ Slavonia – and the Autonomist Party , advocating maintaining autonomy of Dalmatia , opposite to the People 's Party demands for unification of Croatia @-@ Slavonia and Dalmatia . The Autonomist Party , most notably led by Antonio Bajamonti , was also linked to Italian irredentism . By 1900 , the Party of Rights had made considerable gains in Dalmatia . The Autonomists won the first three elections , but all elections since 1870 was won by the People 's Party . In the period 1861 – 1918 there was seventeen elections in the Kingdom of Croatia @-@ Slavonia and ten in the Kingdom of Dalmatia .