The name of the city is derived from celtic belo-dunum which means "splendid hill."[citation needed] The name was inspired by the favorable position within the valley.
The city was founded around 220-200 BC by the Romans and, starting from 181 BC, it became an important military stronghold in the Roman Venetia. After the fall of the Western Roman Empire, it was ruled by the Lombards (6th century) and the Carolingians (8th century); from the late 9th century it was ruled by a count-bishop and it received a castle and a line of walls. Later it was a possession of the Ghibelline family of the Ezzelino. After having longly contended the nearby territory with Treviso, in the end Belluno gave itself to the Republic of Venice (1404). The city was thenceforth an important hub for the transport of lumber from the Cadore through the Piave river.