Bath was ravaged in the power struggle between the sons of William the Conqueror following his death in 1087. The victor, William Rufus, granted the city to a royal physician, John of Tours, who became Bishop of Wells and Abbot of Bath.Shortly after his consecration John bought Bath Abbey's grounds from the king,as well as the city of Bath itself. Whether John paid Rufus for the city or whether he was given it as a gift by the king is unclear. The abbey had recently lost its abbot, Ælfsige, and according to Domesday Book was the owner of large estates in and near the city; it was likely the abbey's wealth that attracted John to take over the monastery. By acquiring Bath, John also acquired the mint that was in the city. In 1090 he transferred the seat, or administration, of the bishopric to Bath Abbey, probably in an attempt to increase the revenues of his see. Bath was a rich abbey, and Wells had always been a poor diocese. By taking over the abbey, John increased his episcopal revenues. William of Malmesbury portrays the moving of the episcopal seat as motivated by a desire for the lands of the abbey, but it was part of a pattern at the time of moving cathedral seats from small villages to larger towns. When John moved his episcopal seat, he also took over the abbey of Bath as his cathedral chapter, turning his diocese into a bishopric served by monks instead of the canons at Wells who had previously served the diocese. John rebuilt the monastic church at Bath, which had been damaged during one of Robert de Mowbray's rebellions. Permission was given to move the see of Somerset from Wells – a comparatively small settlement – to the then walled city of Bath. When this was effected in 1090, John became the first Bishop of Bath, and St Peter's was raised to cathedral status.