According to the "Worldmark Encyclopedia of Nations "and the "Grand Larousse encyclopédique", Croatia entered a personal union with Hungary in 1102, which remained the basis of the Hungarian-Croatian relationship until 1918, while Encyclopædia Britannica specified the union as a dynastic one. According to the research of the Library of Congress, Coloman crushed opposition after the death of Ladislaus I and won the crown of Dalmatia and Croatia in 1102, thus forging a link between the Croatian and Hungarian crowns that lasted until the end of World War I. Hungarian culture permeated northern Croatia, the Croatian-Hungarian border shifted often, and at times Hungary treated Croatia as a vassal state. Croatia had its own local governor, or Ban; a privileged landowning nobility; and an assembly of nobles, the Sabor. According to some historians, Croatia became part of Hungary in the late 11th and early 12th century, yet the actual nature of the relationship is difficult to define. Sometimes Croatia acted as an independent agent and at other times as a vassal of Hungary. However, Croatia retained a large degree of internal independence. The degree of Croatian autonomy fluctuated throughout the centuries as did its borders.