Kammala jumla mai zuwa: Yayin da Illyrians suka cimma burin ɗaga hankalin al'ummar Croatia ta 1850, sun kasa a wasu wurare. A cikin shekarun 1850, HPS da Bishops na Roman Katolika Josip Juraj Strossmayer da Franjo Rački sun goyi bayan ra'ayin Illyrian. Tsoron "Drang nach Osten", sun yi imanin cewa za a iya tsayayya da Jamusanci da Magyarisation ta hanyar haɗin kai tare da sauran Slavs, musamman Serbs. Sun ba da shawarar haɗa kan Croatia, Slavonia, da Dalmatia yayin da Masarautar Triune ta faɗaɗa don haɗa da sauran Slavs na Kudu a Austria (ko Austria-Hungary bayan Yarjejeniyar 1867) kafin shiga cikin sauran gwamnatocin Slavic na Kudu a cikin tarayya ko tarayya. Tsarin da aka gabatar na ƙasashen Croatian ko Slav na Kudu da aka bayyana daban-daban ya haifar da shawarwari don trialism a Austria-Hungary wanda ke ɗaukar tsarin mulkin Slav na Kudu tare da matsayi daidai da Masarautar Hungary. An haɗa Croatia da Slavonia tare da Iyakokin Soja a cikin Croatia-Slavonia a 1881. Duk da haka, rabuwa ya kasance kamar yadda yake tsakanin ƙasashen Crown na Saint Stephen <unk> ɓangaren Hungary na masarautar <unk> yayin da Dalmatia da Istria suka kasance cikin Cisleithania na Austrian. Har ila yau, akwai yawan mutanen Croatian a Bosnia da Herzegovina.
An haɗu da Austria-Hungary a 1908. Haɗin kan waɗannan ƙasashe ya zama babban batun siyasa na Croatia-Slavonia a cikin mahallin trialist.