From 1850 until 1853, he was attached to Forts Sullivan and Preble in Maine, primarily serving on garrison duty. Promotion came relatively slowly in the antebellum army, and officers often resigned to take up civilian pursuits. Duncan Johnson was no exception.
From 1850 until 1853, Duncan Johnson was stationed at Forts Sullivan and Preble in Maine, primarily on garrison duty. In the antebellum army, promotions were slow, and many officers left to pursue civilian careers. This is what happened with Duncan Johnson.