In 147 BC, four years after the end of the Second Celtiberian War, the Lusitanians, who had rebelled between 155 BC and 150 BC, rebelled again in the Viriathic War (147–139 BC). In 144 BC, the fourth year of this war, Viriathus, the Lusitanian leader, incited the Celtiberians to rebel. This led to the Numantine War (143–133 BC), which was the longest war of resistance against the Romans.