Another imperial usurper, Magnus Maximus, raised the standard of revolt at Segontium (Caernarfon) in north Wales in 383, and crossed the English Channel. Maximus held much of the western empire, and fought a successful campaign against the Picts and Scots around 384. His continental exploits required troops from Britain, and it appears that forts at Chester and elsewhere were abandoned in this period, triggering raids and settlement in north Wales by the Irish. His rule was ended in 388, but not all the British troops may have returned: the Empire's military resources were stretched to the limit along the Rhine and Danube. Around 396 there were more barbarian incursions into Britain. Stilicho led a punitive expedition. It seems peace was restored by 399, and it is likely that no further garrisoning was ordered; by 401 more troops were withdrawn, to assist in the war against Alaric I.