After a very checkered past in North Carolina, Coffin moved to Indiana in the 1840s. There he redeemed himself during the Civil War by serving as a spy for the government of Gov. Oliver P. Morton. His southern upbringing and accent allowed him to infiltrate the Knights of the Golden Circle, a pro-Southern group of sympathizers operating in the state. His information allowed the government to keep the group in check and avoid their causing trouble within the state of Indiana during the war years.