In 1075 the king's refusal to sanction this marriage between two powerful families caused a revolt in his absence. The leaders were Ralph, his new brother-in-law Roger de Breteuil, 2nd Earl of Hereford, and Waltheof, 1st Earl of Northumberland. The revolt was plagued by disaster. Waltheof lost heart and confessed the conspiracy to Lanfranc, the Archbishop of Canterbury, who urged Earl Roger to return to his allegiance, and finally excommunicated him and his adherents- Waltheof was later executed by William. Ralph encountered a much superior force under the warrior bishops Odo of Bayeux and Geoffrey de Montbray (the latter ordered that all rebels should have their right foot cut off) near Cambridge and retreated hurriedly to Norwich, hotly pursued by the royal army. Leaving his wife to defend Norwich Castle, he sailed for Denmark in search of help, and eventually returned to England with a fleet of 200 ships under Cnut and Hakon, which failed to do anything effective.