Such acts of aggression were not limited to wars against territorial enemies, but could form part of the strategies of conquest, subjugation and punishment of rebellion. Alexander the Great suppressed a revolt in Thebes, Greece in 335 BC, after which he ordered the city to be torched and laid waste. Alexander ordered (or allowed) a similar arson at Persepolis in 330 BC. It was a policy which was repeated throughout the period. William I of England, following his conquest of England in the 11th century, asserted his control of Northumbria by destructive campaigns throughout the region: "He ordered that crops and herds, tools and food should be burned to ashes. More than 100,000 people perished of hunger", reported Orderic Vitalis, a contemporary chronicler. It was a scene repeated the following century, during the anarchy of Stephen of England's reign. Civil war erupted between Stephen's supporters and those of the Empress Matilda, a rival claimant for the throne. The "Gesta Stephani" tells of the deeds of one of Stephen's supporters, Philip of Gloucester, by describing how he "raged in all directions with fire and sword, violence and plunder", reducing territory to "bare fields and dreadful desert".