 Soon afterwards he was granted total freedom within the confine of the town of Concord, and during these years as a prisoner of war he was able to purchase the Knap estate back in Argyll.On 6 May 1778, he was finally released in exchange for Ethan Allen.Six months after his release, Campbell was ordered to lead 3,000 men from New York to Georgia, and in late December his army won the Battle of Savannah, followed by another victory at Augusta, Georgia.