Isaac Monroe Brantley was born May 4, 1841 in Walton Count, Georgia. He was the son of Henry T. and Sarah (Hendrick) Brantley. He mustered on 21 birthday. Isaac married Letty Braswell 10/9/1865 in Walton County, Georgia. He and Letty had nine children.

He died in Chilton County , Alabama on September 1, 1929.