BRIGADIER GENERAL MARK J. O’NEIL
DEPUTY COMMANDING GENERAL OF OPERATIONS
10TH MOUNTAIN DIVISION (LIGHT INFANTRY)
Brigadier General Mark J. O’Neil graduated from Norwich University and commissioned as an Infantry Officer on 28 May 1986. Prior to assuming duty as the Deputy Commanding General - Operations, 10th Mountain Division, he served as the Executive Officer to The Chief of Staff, United States Army.
BG O’Neil began his career as a Platoon Leader, Company Executive Officer, and Scout Platoon Leader with 1st Battalion, 5th Cavalry Regiment, 1st Cavalry Division, Fort Hood, Texas. Beginning in February of 1991, BG O’Neil served as a Battalion Logistics Officer and later Rifle Company Commander with 1st Battalion, 27th Infantry Regiment, 25th Infantry Division, Schofield Barracks, Hawaii. In April 1994, BG O’Neil joined 3rd Battalion, 75th Ranger Regiment, Ft. Benning, GA, where he served as a Battalion Training Officer, Assistant Operations Officer, and Rifle Company Commander, and later as a Liaison/Plans Officer with Headquarters and Headquarters Company, 75th Ranger Regiment.
In June 1998, Brigadier General O’Neil joined a special operations organization where he initially served as a Squadron Operations Officer. He served in every key leadership position within the organization from Troop Commander, Selection and Training Commander, Squadron Commander, Deputy Commander for Operations, and finally as the Commander of the organization from July 2009 to July 2011. Additionally, in July 2004, Brigadier General O’Neil was assigned to the Joint Special Operations Command where he served as the Chief, Current Operations Division.
Brigadier General O’Neil’s deployments while serving in the aforementioned positions include peacekeeping operations in Bosnia and 15 deployments in support of overseas contingency operations in Afghanistan for Operation Enduring Freedom and Iraq for Operation Iraqi Freedom and Operation New Dawn.
Brigadier General O’Neil is a graduate of numerous military courses during his career and most recently a graduate of the Senior Service College (CIA Fellowship).
Brigadier General O’Neil’s military awards and decorations include the following: Defense Superior Service Medal, Legion of Merit (with 1 Oak Leaf Cluster), 7 Bronze Star Medals (1 with Valor device), Defense Meritorious Service Medal (with 1 Oak Leaf Cluster), Meritorious Service Medal (with 1 Oak Leaf Cluster), Joint Service Commendation Medal, Army Commendation Medal (with 2 Oak Leaf Clusters), Ranger Tab, Combat Infantryman Badge, Expert Infantryman Badge, Military Free Fall Jumpmaster Badge, Master Parachutist Badge, and the Air Assault Badge.