Liburnia (Λιβουρνία) in ancient geography was the land of the Liburnians, a region along the northeastern Adriatic coast in Europe, in modern Croatia, whose borders shifted according to the extent of the Liburnian dominance at a given time between 11th and 1st century BC. Domination of the Liburnian thalassocracy in the Adriatic Sea was confirmed by several Antique writers, but the archeologists have defined a region of their material culture more precisely in northern Dalmatia, eastern Istria, and Kvarner.
The Liburnian cultural group developed at the end of the Bronze Age after the Balkan-Pannonian migrations, and during the Iron Age in a region bordered by Raša, Zrmanja and Krka rivers (Arsia, Tedanius, Titius), including the nearby islands. This territory lay mostly at the coast and on the numerous islands. Its continental borders were marked by the rivers and mountains: Raša, Učka, Gorski Kotar, peaks of Velebit mountain (Mons Baebius), Zrmanja and Krka, with a small area northeast of Krka bordered by Butišnica, Krka, Kosovčica and Čikola, around the city Promona (modern Tepljuh near Drniš). Thus, it neighbored in the northwest with the Histri, in the north with the Iapodian and in the southeast with the Dalmatian cultural groups.
Liburnian culture had distinct features and differed considerably from those of its neighbors. Its isolation and special qualities resulted primarily from its geographical isolation from the hinterland and its seaward orientation, important for traffic circulation and territorial connection. Maritime focus shaped Liburnian ethnic development on the Indo-European basis with the transfer of Mediterranean cultural traditions into an independent ethnic community, separated from neighboring peoples, but having evident similarities and links with the wider Illyrian and Adriatic territories. The Liburnians' skillful seamanship allowed them to hold navigable routes along the eastern Adriatic coast with strategic points, such as the islands of Hvar and Lastovo in the central Adriatic and Corfu (8th century BC) in the Ionian Sea, while they already had colonies at the western Adriatic coast, especially in region of Picenum, from the beginning of the Iron Age.