Guthrum and the Danes brokered peace with Wessex in 876, when they captured the fortresses of Wareham and Exeter. Alfred laid siege to the Danes, who were forced to surrender after reinforcements were lost in a storm. Two years later, Guthrum again attacked Alfred, surprising him by attacking his forces wintering in Chippenham. King Alfred was saved when the Danish army coming from his rear was destroyed by inferior forces at the Battle of Cynuit. The modern location of "Cynuit" is disputed but suggestions include Countisbury Hill, near Lynmouth, Devon, or Kenwith Castle, Bideford, Devon, or Cannington, near Bridgwater, Somerset. Alfred was forced into hiding for a time, before returning in the spring of 878 to gather an army and attack Guthrum at Edington. The Danes were defeated and retreated to Chippenham, where King Alfred laid siege and soon forced them to surrender. As a term of surrender, King Alfred demanded that Guthrum be baptised a Christian; King Alfred served as his godfather.