The primary reason for Alfred's victory was probably the relative size of the two armies. The men of even one shire could be a formidable fighting force, as those of Devon proved in the same year, defeating an army under Ubbe Ragnarsson at the Battle of Cynwit. In addition, in 875 Guthrum had lost the support of other Danish lords, including Ivar and Ubba. Further Danish forces had settled on the land before Guthrum attacked Wessex: in East Anglia, and in Mercia between the treaty at Exeter and the attack on Chippenham; many others were lost in a storm off Swanage in 876–877, with 120 ships wrecked. Internal disunity was threatening to tear the Danes apart, and they needed time to reorganize. Fortunately for Wessex, they did not use the time available effectively.