In 310, Maxentius lost Istria to Licinius, who could not continue the campaign. However, by the middle of 310 Galerius had become too ill to involve himself in imperial politics and he died soon after April 30, 311. Galerius' death destabilized what remained of the Tetrarchic system. On hearing the news, Maximinus mobilized against Licinius, and seized Asia Minor before meeting Licinius on the Bosphorus to arrange terms for peace. In the meantime, Maxentius fortified northern Italy against potential invasions and sent a small army to Africa under the command of his praetorian prefect Rufius Volusianus which defeated and executed the usurper Domitius Alexander in 310 or 311. Maxentius used the opportunity to seize the wealth of his supporters, and to bring large amounts of grain to Rome. He also strengthened his support among the Christians of Italy by allowing them to elect a new Bishop of Rome, Eusebius.