Aidan Breandán Stiles was born on Eglin Air Force Base in Florida to an American father, Jason Stiles, and an Irish-born mother, Máire O'Mara-Stiles. His father was an intelligence officer in the U.S. Air Force and as a consequence, he was raised all over the world. After graduating from high school, Stiles went on to the Virginia Military Institute. He graduated from VMI with a Bachelor of Arts of International Studies and a commission as a Second Lieutenant in the United States Marine Corps via the Naval Reserve Officers Training Corps. While at VMI, Stiles decided to become a ground intelligence officer.