Glenn Colwell was the son of Glenn and Sarah (Moore) Colwell, born in Pike or Spalding, Georgia in 1831. Glenn was married to Polly McKneely in 1852 and they became the parents of five children over the next ten years. The 1860 census lists Glenn as a farmer - 1st year, in Spalding, Georgia.
Glenn enlisted in the 53rd Georgia Infantry in April 1862. He was captured at Sharpsburg in September of that year and later exchanged. He died of pneumonia at Lynchburg, Virginia in May 1864 and is buried at the Confederate Cemetery there. A stone in his memory was placed at Rehobeth Baptist Church in Griffin, Georgia, the church attended by his widow and children.