William A. Egger was born around 1839 in Mississippi to Mary Egger. His father died sometime before 1850. He grew up and attended school in Lowndes County, Mississippi, and by 1860, he was working as a farmer. He enlisted in the Confederate army on August 1, 1861, in Caledonia, Mississippi, and he mustered in as a private in Company E of the 24th Mississippi Infantry on October 11. The regiment took part in the siege of Corinth. In late 1862, army officials detailed him to hospital duty in Dalton, Georgia. He remained in the army until at least August 1863, and he died sometime afterwards.