The joint rule of Maxentius and Maximian in Rome was tested further when Galerius himself marched to Italy in the summer of 307 with an even larger army. While negotiating with the invader, Maxentius could repeat what he did to Severus: by the promise of large sums of money, and the authority of Maximian, many soldiers of Galerius defected to him. Galerius was forced to withdraw, plundering Italy on his way. Some time during the invasion, Severus was put to death by Maxentius, probably at Tres Tabernae near Rome (the exact circumstances of his death are not certain). After the failed campaign of Galerius, Maxentius' reign over Italy and Africa was firmly established. Beginning in 307 already, he tried to arrange friendly contacts with Constantine, and in the summer of that year, Maximian travelled to Gaul, where Constantine married his daughter Fausta and was in turn appointed Augustus by the senior emperor. However, Constantine tried to avoid breaking with Galerius, and did not openly support Maxentius during the invasion.