Raymond Anthony Glenn was born October 18, 1898, to John Edward and Mary Agnes Glenn in Frankfort, Kentucky. He was drafted and served in the Army during WWI.
When he began acting in the 1920s, he took up the screen name of Bob Custer, although he still used his real name in a few non-western films. His career lasted from about 1924 to 1937. Used to acting stiffly and with an untrained voice, Custer found himself in the same place many of his peers did—having difficulty transitioning from silent films to talkies. But he still starred in such films as "Law of the Rio Grande," "Mark of the Spur, and "Ambush Valley" with sound. After retiring from the industry, he became a building inspector; eventually Chief Building Inspector for the city of Newport, California.
Custer was married twice and had one son. His first wife, Anne Elizabeth Cudahy, was very wealthy—as was Custer, especially before the depression—and they lived lavishly during their six-year marriage. They divorced in 1933, and Bob wouldn't marry again until 1948, when he and Mildred Boughers, a girl twenty-seven years his junior, tied the knot. Their marriage lasted through to his heart attack in 1974, when he died at the age of seventy-six.
Bob Custer may not have been the screen's greatest Western actor, but long before I'd even seen Roy Rogers, Gene Autry, John Wayne, or any of the other greats, I was enthralled with "The Law of the Wild," a twelve-chapter serial that Custer starred in along with Rin Tin Tin and Rex ("king of the wild stallions"). I loved the typical serial action—the fist fights, the horse fights, the chases. Bob Custer was my first real "Cowboy Hero."
Sources:
The Old Corral: Bob Custer
IMDb: Bob Custer
Find A Grave: Bob Custer