Lieutenant Colonel Donlon is a native of Bethesda, Maryland. He graduated from the University of Virginia in May 2002 and reported to The Basic School in June 2002.
Lieutenant Colonel Donlon graduated from The Basic School in January 2003 and from the Infantry Officer Course in May 2003. He reported to 2d Battalion, 6th Marines in June 2003.
While in 2d Battalion, 6th Marines, Lieutenant Colonel Donlon served as a Rifle Platoon Commander in Echo Company and CAAT Platoon Commander in Weapons Company. He deployed three times: Unit Deployment Program to Okinawa from September 2003 to April 2004; Baghdad, Iraq from September 2004 to March 2005; and Fallujah, Iraq from September 2005 to April 2006. In June 2006, he reported to The Basic School.
While at The Basic School, Lieutenant Colonel Donlon served as the Infantry Platoon Commander in Combat Instructor Company and at the Infantry Officer Course as an Instructor and Class Advisor. In August 2009, he reported to Expeditionary Warfare School.
Graduating early from Expeditionary Warfare School, Lieutenant Colonel Donlon reported to 3d Battalion, 8th Marines in April, 2010. While in 3d Battalion, 8th Marines, he served as the Company Commander of India Company and Battalion Operations Officer. He deployed twice: from August 2010 to May 2011 on the 26th Marine Expeditionary Unit, operating in the Upper Gereshk Valley of Helmand Province, Afghanistan; and, from April to November 2012, in Marjah, Nawa, Garmsir, and Khanashin Districts, Helmand Province, Afghanistan. In May 2013, he reported to Recruiting Station San Diego.
Lieutenant Colonel Donlon served as Commanding Officer, Recruiting Station San Diego, from June 2013 to June 2016. In July 2016, he reported to the School of Advanced Warfighting, graduating in June 2017.
Lieutenant Colonel Donlon reported to the III MEF Command Element, G5 (Plans) in July 2017. In Okinawa, he served as Lead MAGTF Planner, Pacific Plans. until detaching from III MEF and returning to 2d Marine Division in May 2019.
Lieutenant Colonel Donlon holds a Bachelor of Arts in History and Master of Teaching in Secondary Social Studies from the University of Virginia and a Master of Operational Studies from Marine Corps University. He is a distinguished graduate of The Basic School, Expeditionary Warfare School, and the Marine Corps Command and Staff Distance Education Program. He graduated from the School of Advanced Warfighting as the General Clifton B. Cates Award recipient.