Lieutenant Colonel Stewart is a native of San Diego, California. He served as an enlisted Marine from 1998 to 2006 and attained the rank of Staff Sergeant. He commissioned via the Marine Enlisted Commissioning Education Program in May 2006.

Command assignments include Weapons Platoon Commander, 1st Battalion, 5th Marine Regiment; Weapons Company Commander, 1st Battalion, 7th Marine Regiment; Headquarters and Service Company Commander, 1st Battalion, 7th Marine Regiment; Commanding Officer Recruiting Station Phoenix, 8th Marine Corps District.

Staff assignments include Company Executive Officer, Alpha Company, 1st Battalion, 5th Marine Regiment; Firepower Control Team Leader, 1st Air Naval Gunfire Liaison Company; Assistant Operations Officer, 1st Battalion, 7th Marine Regiment; Company Grade Infantry Monitor, Manpower Management Officer Assignments; Executive Officer, 1st Battalion, 7th Marine Regiment; Maneuver Section Officer in Charge, Tactical Training and Exercise Control Group; and Operations Officer, Tactical Training and Exercise Control Group.

He has deployed in support of the 31st Marine Expeditionary Unit (Special Operation Capable), 11th Marine Expeditionary Unit, Operation ENDURING FREEDOM (Afghanistan), and Marine Rotational Forces - Darwin.  

He is a graduate of The Basic School (2006), Infantry Officer Course (2007), Marine Corps Expeditionary Warfare School (2013), Marine Corps Command and Staff College Distance Education Program (2017). He holds a Bachelor of Arts degree from The Pennsylvania State University (2006) and a Masters of Arts from Marshall University (2017).  

His personal decorations include the Bronze Star Medal with Combat Distinguishing Device, Meritorious Service Medal (2), Navy and Marine Corps Commendation Medal with Combat Distinguishing Device (3), Navy and Marine Corps Achievement Medal (3), Combat Action Ribbon, and Good Conduct Medal (2).