The empire faced new waves of mass migrations likely triggered by the Huns' westward expansion. Around 405, a mixed group of peoples invaded Italy under the command of a Gothic chieftain Radagaisus, but Stilicho overcame them at Florence. On 31 December 406, tens of thousands of Vandals, Alans, Suebi, Sarmatians and "hostile Pannonians" crossed the Rhine into Gaul. Insecurity led to insurrections in Britain, and the rebellious troops proclaimed their commanders emperors, but only one of them, Constantine III could consolidate his position. He crossed the Channel and restored peace along the Rhine through treaties with the Franks, Alemanni and Burgundians. The western crisis compromised Stilicho's position.