Thomas served as a private in Company "B" 47th Illinois Volunteer Infantry. His widow received a pension as an Army Widow.
From the Daily Review, Decatur, IL, Friday, 15 Sep 1911, pg. 14: Another Veteran Dies. Thomas J. Barnum - Served In Forty-Seventh Illinois Volunteers During War. Thomas J. Barnum died at 10:46 Thursday night at the family residence, 1362 North Main street. He was aged sixty-eight years. He came to Decatur six years ago from Gillman, Illinois and this has been his home ever since. He was a member of the First Methodist church of this city. Mr. Barnum was born at Morton, Tazewell County, March 8, 1848. He was the son of William R. and Mahala Barnum. With his parents he moved to Onargo, Illinois, when he was a little boy. June 30, 1870, at Wateska, he was united in marriage with Miss Emma Reed, daughter of Mr. and Mrs. William Reed of Onargo. One son and three daughters were born to them, Maude, died in infancy and Mrs. Daisy N. Stough died in maturity. The surviving children are Leroy C. Barnum of Gowrie. Ia, and Mrs. Elsie R. Ohman of Decatur. He also leaves one brother and four sisters, William Calvin Barnum of Canton, Kan., Mrs. Jane Parker of Peoria. Mrs. Luella Hoke of Crescent City, Ill., Mrs. Effie Roberts of Covina, Cal., and Mrs. Carrie Murphy of Lennox, Ia. He also leaves a granddaughter, Mrs. Ora B. Stough of Decatur. Mr. Barnum was a member of company B, Forty-seventh infantry, enlisting at Peoria and serving through three years of the Civil War. He was a member of Dunham Post 141, O. A. 33. After the close of the war he engaged in farming near Gilman, where he remained until moving to Decatur six years ago. The funeral will be held at 2:30 Sunday afternoon at the family residence, 1362 North Main Street. The services will be conducted by Rev. J. C. Willits. The interment will be in Greenwood. Friends may call between 2 and 4 P M.
Burial:
Greenwood Cemetery
Decatur
Macon County
Illinois, USA.