Aaron Hinman Grout (January 18, 1879 – December 29, 1966) was an American judge and political figure who served as Secretary of State of Vermont.

Enlisting in Company I, 1st Vermont Infantry Regiment as a private, he attained the rank of corporal before receiving his commission as a captain and serving as an aide to brigade commander Brigadier General Julius J. Estey.

During the Spanish–American War, he aided Estey in organizing and mustering the National Guard soldiers who made up the unit federalized as the 1st Vermont Volunteer Infantry Regiment.

[4] Grout graduated from the University of Vermont in 1901, studied law with Newport attorney John W. Redmond, and attained admission to the bar in 1904.

He served as Secretary of Civil and Military Affairs (chief assistant) to Governor George H. Prouty (1908 to 1910).

[8] During his service on Governor Prouty's staff, Grout also served as Prouty's military secretary with the rank of major, and he continued his military service after 1910 as the Judge Advocate of the Vermont National Guard.

[9] During World War I, he was a lieutenant colonel in the Vermont Volunteer Militia, the home guard organization formed to handle the National Guard's domestic missions while its soldiers were deployed overseas.

[12] Grout resigned as Secretary of State to relocate to Burlington and become Treasurer and Manager of the Vermont Acceptance Corporation, a company that made loans to finance the purchase of homes, automobiles and other items.