Alduin, Auduin, or Audoin was king of the Lombards from 546 to 560. Under him the Lombards became fœderati of the Byzantines (541), signing a treaty with Justinian I which gave them power in Pannonia and the north. Beginning in 551, Audoin was obliged to send troops to serve Narses in Italy in the Gothic War against the Ostrogoths. The next year (552), he sent over 5,000 men to defeat the Goths on the slopes of Vesuvius. He died in 563 or 565 and was succeeded by his son, Alboin, who brought the Lombards into Italia.