Robert Livingston Armstrong
- Bats Unknown, Throws Unknown
- Height 6' 2", Weight 160 lb.
- Debut June 26, 1871
- Final Game August 29, 1871
- Born July 4, 1850 in Baltimore, MD USA
- Died December 3, 1917 in Fort Worth, TX USA
Robert Armstrong played 12 games for the Fort Wayne Kekiongas of 1871, a team whose season consisted of 19 games. Armstrong was in center field for 11 of his 12 games. Little was known about him for the longest time, except that he was originally from Baltimore, MD, and was approximately 21 when he appeared in the National Association. Research by Bruce Allardice of SABR traced him to Fort Worth, TX, and discovered that he was a member of the "Society of Cincinnati of Philadelphia", an association of descendants of Revolutionary War veterans (his great-grandfather was Major John Armstrong, who fought in the war). That confirmed that he was the son of John Horatio Armstrong of Baltimore. He worked in the county clerk's office and there is an account in the Fort Worth Gazette of his taking part in a game between the "lawyers" and the "court house" in 1895. This additional information made it possible to trace his birth and death details, as well as his full name.
- "Robert Armstrong Found", in Bill Carle, ed.: Biographical Research Committee Report, SABR, March/April, 2017, p. 1.