Lieutenant Colonel Brian T. Geisen is a native of Pensacola, FL. He graduated from the Naval Academy in 2008 and was commissioned in the United States Marine Corps. After completing the Basic School, he was designated a Logistics Officer.
In 2009, 2ndLt Geisen reported to Headquarters Battalion, 2d Marine Division, Camp Lejeune, NC. He served as a Truck Platoon Commander. In 2011, 1stLt Geisen deployed to Afghanistan where he served in a myriad of billets to include Platoon Commander and Base Realignment and Closure Liaison Officer. Following his deployment, 1stLt Geisen was assigned as Executive Officer, Headquarters Company, 2d Marin Division.
In 2012, Capt Geisen reported to Marine Corps Detachment Fort Lee, VA. There he served as the Detachment Logistics Officer, Detachment Executive Officer, and Company Commander. In 2016, he attended and graduated from resident Logistics Captains Career Course, Army Logistics University, Fort Lee, VA.
In 2016, Capt Geisen returned to Camp Lejeune, NC to serve as the Combat Logistics Regiment 2 Logistics Officer. In 2016, he led a detachment of Marines in Norway to enable NATO Exercise Saber Strike. He deployed to EUCOM in 2016 as the Special Purpose Marine Air Ground Task Force - Crisis Response Africa (SPMAGTF-CR-AF) Logistics Combat Element Operations Officer as a member of Combat Logistics Battalion 8. He redeployed to EUCOM in 2017, as the SPMAGTF-CR-AF Command Element Liaison Officer to Marine Forces Europe and Africa. Finally, he served as the 2d Transportation Support Battalion Operations Officer where he led a detachment of Marines in support of MPSRON operations aboard Blount Island Command, FL.
In 2020, Major Geisen attended Command and Staff College, Marine Corps University, Quantico, VA. Following, he served three years at Combat Development and Integration (CD&I), Quantico, VA in the following billets: Deputy Director Transportation Branch; Force Design Planner; and Aide de Camp to Deputy Commandant, CD&I.
In July 2024, LtCol Geisen reported to Combat Logistics Regiment 2 as the Operations Officer. In 2025, he deployed as the J-3 Director, Joint Task Force SOUTHERN GUARD in support of Department of Homeland Security operations in Guantanamo Bay, Cuba.
LtCol Geisen has a Masters in Business Administration, Masters in Military Studies, Lean Six Sigma Black Belt, and MIT Systems Engineering Certification. His personal awards include the Meritorious Service Medal with two gold stars, Navy and Marine Corps Commendation Medal, Joint Service Achievement Medal, Navy and Marine Corps Achievement Medal, and multiple unit awards. He has also earned the Navy and Marine Corps Parachutist Badge.