After a civil war broke out between Mark Antony and Augustus, the legion sided with Antony and fought for him in the lost battle of Mutina. When the two men later decided to cooperate, they defeated the murderers of Caesar in the battle of Philippi. The V Alaudae was there. The legion participated in Antony's war against the Parthian empire. Antony employed the legion also during his campaign against Octavian, which culminated in the naval battle off Actium, where Antony was defeated. Augustus transferred the V Alaudae to Mérida in Lusitania after 30 BC, where it took part in the campaigns against the Cantabrians.