Colonel Donald J. Marnon was commissioned an Infantry Officer upon graduation from Officer Candidate School 25 June 1958, Class Number OC-3. His first duty assignment was as Rifle Platoon Leader, Company C, 1st Battle Group, 29th Infantry. | His subsequent duty assignments include: 2d Infantry Division, Fort Benning, Georgia; 7th Special Forces, Fort Bragg, North Carolina; 8th Special Forces, Panama Canal Zone; District Senior Advisor, Vietnam; Small Arms Test Officer, C, Supporting Weapons Test Division Operations Officer, U.S. Army Infantry Test Board, Fort Benning, Georgia; Senior Advisor, 1st Airborne Battalion, Vietnamese Airborne Division, Vietnam; Chief, Fort Benning Ranger Committee, Fort Benning, Georgia; Chief, Inspection Branch, Office of the Inspector General, Fort Benning, Georgia; Exchange Instructor, Canadian Forces Command and Staff College, Toronto, Canada; Executive Officer, USA Natick Res and Development Command, Natick, Massachusetts; Deputy Commander/SA to Commander, USA Natick Research and Development Command, Natick, MA; Chief, DARCOM Office of the Individual Soldier, Natick, MA; Director of Industrial Operations, USAIC, Fort Benning, Georgia.; Garrison Commander, Fort Rucker, Alabama.
He served as the City Manager, Dothan, Alabama from 1987 to 1994. | Military schools attended include:  Airborne, Ranger, Pathfinder, Jungle Warfare, Special Forces Officer Course, Defense Language Institute (Spanish), Officer Career Course, Defense Language Institute (Vietnamese), Command and General Staff College. | His awards and decorations include: Silver Star, Bronze Star with V with 3 Oak Leaf Clusters, Meritorious Service Medal, Air Medal with 2 Oak Leaf Clusters, Air Medal with 2 Oak Leaf Clusters, Army Commendation Medal with 1 Oak Leaf Cluster, Vietnam Service Medal with 8 Battle Stars, Good Conduct Medal, Ranger Tab, Pathfinder Tab, Master Parachutist Wing, CIB.
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