Ira Aten was born on 3 September 1862 in Illinois. Aten’s father, Austin Aten, a Methodist minister circuit rider, moved the family to Texas in 1876, settling near Round Rock. In 1878 Ira witnessed the death of outlaw Sam Bass. Listening to the Texas Rangers present, young Aten decided to become a lawman.
Aten joined the Texas Rangers in March 1883. He became a member of Company D under Capt. L. P Seiker and later served as Sergeant under Frank Jones. He served as a Regular Ranger for over six years and then as a Special Ranger (volunteering without pay) until 1891. Most of his work was in the counties bordering the Rio Grande, roughly from Pecos to Rio Grande City.