While the historian J. B. Bury conjectured that rebellion of the British legions in 406 was aimed principally at Stilicho, the emperor Honorius’s "magister militum", the ancient sources (Olympiodorus of Thebes, Zosimus and Orosius) generally link the rebellion to the barbarian incursions into Gaul and Italy, and specifically the Vandal and Alanic tribes that crossed the Rhine frontier, which Prosper of Aquitaine dated to 31 December 406. The debate for modern historians has therefore centred on whether this event was the trigger for the rebellion. Historians such as N. H. Baynes and M. Kulikowski contend that the rebellion was triggered by the crossing of the Rhine, which should be therefore dated to 31 December 405. However, others such as F. Paschoud and Anthony Birley argue that Prosper’s date is accurate, and that the events in Gaul that sparked the rebellion were related to the barbarians who entered Gaul from Italy, probably a part of the army of Radagaisus, who invaded Italy in 405/6.