Lieutenant Colonel John P. O’Sullivan was commissioned as an Ordnance Officer in 2001 from the Old Dominion University ROTC program and is a native of Montclair, Virginia. 

Upon completion of Ordnance Officer Basic Course in July of 2002, Lieutenant Colonel O’Sullivan served in numerous assignments beginning at the 19th Signal Maintenance Company and 556th Maintenance Company as Company Executive Officer, Platoon Leader, and Shop Officer at Ft. Huachuca, AZ until July of 2005.  From March 2006 until January 2011, he served as Battalion S4 for the 505th Quartermaster Company, commander of Echo Company, 1st Battalion, 1st Air Defense Artillery (PAC III), and the Group Support Operations (SPO) Distribution Officer at the 10th Support Group, all in Okinawa, Japan. 

As a field grade officer, Lieutenant Colonel O’Sullivan served as SPO Maintenance Officer, Forward Logistics Element (FLE) Officer, and Supply and Services (S&S) Officer in the 10th Sustainment Brigade in Ft. Drum, New York from 2011-2013.  From 2013-2016, he completed his Key Developmental assignments from Ft. Bliss as the 401st Army Field Support Brigade (AFSB) SPO forward in Bagram, Afghanistan, and the Executive Officer of the 142D Combat Sustainment Support Battalion (CSSB).  From 2016-2020, he served with the Joint Multinational Readiness Center (JMRC) as the Brigade Sustainment Observer, Coach, Trainer (OCT), the Operations Group S4, and culminating as Chief of Staff.  

His three combat deployments include:  leading a Maintenance Support Team to Camp Victory, Iraq for 12 months in 2003-2004 while assigned to the 19th Signal Maintenance Company; leading a FLE in Kabul, Afghanistan for nine months and S&S Officer in Bagram, Afghanistan for three months in 2011-2012 while serving in the 10th Sustainment Brigade; serving as Brigade SPO for the 401st AFSB in Bagram, Afghanistan for six months in 2014.

Lieutenant Colonel O’Sullivan’s military education includes the Ordnance Officer Basic Course, the Logistics Captains Career Course, and the Command and General Staff Officer Course.  His civilian education includes a Bachelor of Arts degree in History from Old Dominion University and a Master’s Degree in International Relations from Troy University.

His awards and decorations include the Bronze Star Medal with one Oak Leaf Cluster, Meritorious Service Medal with two Oak Leaf Clusters, Army Commendation Medal with two Oak Leaf Clusters, Army Achievement Medal with three Oak Leaf Clusters, National Defense Service Medal, Afghan Campaign Medal, Global War on Terrorism Expeditionary Medal, Global War on Terrorism Service Medal, Army Service Ribbon, Overseas Service Ribbon (4th Device), and the NATO medal; he was also awarded the Distinguished Order of Saint Barbara (Air Defense Artillery) and the Distinguished Order of Samuel Sharp (Ordnance).

In September 2011, Lieutenant Colonel O’Sullivan married the former Michelle Danielson of Okinawa, Japan and they have two daughters, Emi (6) and Lucca (3).