In 144 BC, Viriathus formed a league against Rome with several Celtiberian tribes and persuaded them to rise against Rome too, in the Second Numantine War. Viriathus' new coalition bested Roman armies at the Second Battle of Mount Venus in 144 BC and again at the failed Siege of Erisone. In 139 BC, Viriathus was finally killed in his sleep by three of his companions who had been promised gifts by Rome. In 136 and 135 BC, more attempts were made to gain complete control of the region of Numantia, but they failed. In 134 BC, the Consul Scipio Aemilianus finally succeeded in suppressing the rebellion following the successful Siege of Numantia.