Under pretence of siding with Vespasian, Civilis of Batavia had taken up arms and induced the inhabitants of his native country to rebel. The rebelling Batavians were immediately joined by several neighbouring German tribes including the Frisii. These forces drove out the Roman garrisons near the Rhine and defeated a Roman army at the Battle of Castra Vetera, after which many Roman troops along the Rhine and in Gaul defected to the Batavian cause. However, disputes soon broke out amongst the different tribes, rendering co-operation impossible; Vespasian, having successfully ended the civil war, called upon Civilis to lay down his arms, and on his refusal his legions met him in force, defeating him in the Battle of Augusta Treverorum.