Henry Rust Jr. was born 12/2/1833 at Norway, Maine, to Henry Rust and Mary L. Stowell. His wife's name was Katherine Hobbs and they had at least one child, Katherine Louisa, born in 1873. He was a surveyor by profession.
He enlisted as the Lieutenant Colonel of the regiment and was promoted to Colonel to replace Neal Dow on 6/3/1862. Previously he had served as the 1st Lieutenant of Co. G, 1st Maine Infantry and as the Captain of Co. G, 10th Maine Infantry.
He seemed to have been a more popular Colonel than either Neal Dow or Frank Hesseltine, who were also leaders of the 13th Maine at various times.
He was also a very competent officer and frequently was assigned to higher levels of command and staff on several different occasions. In each instance the men of the regiment were glad to see him return.
He died on July 21, 1881, at Haverhill, Massachusetts.