 Following the rise of the Principality of Hungary in the mid 890s, no further Slavic rulers were recorded in the territory until the mid 920s when the Duke of Croatia Tomislav united the territory with Dalmatian Croatia to form the Kingdom of Croatia.There has remained a general uncertainty and dispute over the relationship between the Croatian and Hungarian kingdoms in the 10th and 11th century, with Croatian historian Ferdo Šišić and his followers assuming Tomislav of Croatia had ruled most of the area inhabited by Croats, including Slavonia, while the Hungarian historians Gyula Kristó, Bálint Hóman and János Karácsonyi thought the area between Drava and Sava belonged neither to Croatia nor to Hungary at the time, an opinion that Nada Klaić said she would not preclude, because the generic name "Slavonia" (lit.the land of the Slavs) may have implied so.