 The city of Ragusa was founded by such survivors from Epidaurum.According to the work "De Administrando Imperio" written by the 10th-century Byzantine Emperor Constantine VII, the Croats had arrived in what is today Croatia, from southern Poland, south of Kraków in the early 7th century, however that claim is disputed and competing hypotheses date the event between the 6th and the 9th centuries.Eventually two dukedoms were formed—Duchy of Pannonia and Duchy of Dalmatia, ruled by Liudewit and Borna, as attested by chronicles of Einhard starting in the year 818.