Washington Randle was born around 1824 in Albemarle County, Virginia. By 1850, he was living in Hamilton, Ohio, with his wife Ellen, his 3-year-old daughter Arabella, and his newborn son Elisha. He enlisted in the Union army as a free man on October 24, 1864, for a period of one year. He mustered into Company A of the 12th USCT Infantry Regiment later that day. His enlistment records describe him as 5 feet, 10 inches tall, with black hair, black eyes, and a black complexion. The army quickly assigned the regiment to railroad guard duty in Tennessee and Alabama on the Nashville & Northwestern Railroad line. 

The men took part in operations against Confederate General John Bell Hood's Army of Tennessee, helping repulse Hood's attack on Johnsonville, Tennessee, in early November. On November 24, they saw action at Buford's Station on the Nashville & Northwestern Railroad while performing guard duties. Shortly afterward, the army moved Randle and his comrades to Clarksville, Tennessee, where they participated in a skirmish on December 2. They also took part in the Battle of Nashville on December 15-16. They then pursued Hood to the Tennessee River, seeing action at Decatur, Alabama, at the conclusion of the chase on December 27-28. Following the campaign, the army reassigned the regiment to garrison duty in the Department of the Cumberland.

Randle mustered out on October 27, 1865, in Nashville, Tennessee, once the term of his enlistment expired. The details of his postwar life remain unclear.