While he was emperor, Aurelian overcame the armies of several groups of barbarians – the Goths, Vandals, Juthungi, Sarmatians, and Carpi. Aurelian increased the importance the god Sol Invictus in Roman religion and he built a temple for the god in the city of Rome. For the first time in many centuries, Rome needed a defensive wall to keep out enemies who might attack it. Aurelian's government started to build the Aurelian Walls around Rome. Aurelian's wife, Ulpia Severina, was his (empress) after summer 274. Aurelian was murdered by some of his soldiers in autumn 275.