Mustered into service as a Private on July 29th, 1861
Private Baker was discharged for disability on April 2nd, 1862 because of a severe case of hepatitis. On July 17th, 1862 he mustered into Company A of the 70th Indiana Infantry where he served until the end of the war mustering out on June 8th, 1865
He filed for a pension in February of 1878 and by July of 1886 his wife Sarah E. Baker filed for a "Widows" pension while living in Indiana. Isaac died sometime before that date.
Unknown date of death or burial location.