Returning to Wisconsin in 1865, Watrous worked as the editor of the Black River Falls Jackson County Banner for several years, before moving to edit the Fond du Lac Commonwealth in 1869.

When the American Civil War began, Watrous enlisted in Company E of the 6th Wisconsin Volunteer Infantry Regiment.

[1] During the war, he rose to become a sergeant, and briefly attained the rank of adjutant general of the Iron Brigade.

Returning to Wisconsin after the Spanish–American War, Watrous devoted time to writing works on history and the military.

This article incorporates text from the 1909 edition of Memoirs of Milwaukee County, by Jerome Anthony Watrous which is in the public domain in the United States.