The monastic community at Durham was founded by bishop William of St Calais in 1083. Its arrival from Jarrow and Wearmouth was accompanied by an act of aggression, when the secular clerks previously in residence were presented with the ultimatum of either becoming monks or leaving. All but one chose to leave. This action can be seen as setting the tone for the community’s attitude to the world outside the see. In their historical writings, particularly Symeon’s Historia Dunelmensis Ecclesiae, written between 1104 and 1109, the Durham monks were self-assertive and defensive.