A native of Deerfield, IL, Col Schaefer enlisted in the Marine Corps Reserve in February 1995. After completing a Bachelor of Science degree in Manufacturing Engineering from Western Illinois University, he was commissioned in December 1999.

Upon completing The Basic School in June 2000, he reported to Pensacola, FL to attend the Naval Cryptologic Officer Basic Course. In December 2000, Col Schaefer reported to 1st Radio Battalion as a Signals Intelligence Officer (MOS: 0206). During his tour at Radio Battalion, Col Schaefer deployed in support of the 31st Marine Expeditionary Unit and Operation Iraqi Freedom.

From January 2005 to July 2007, Col Schaefer commanded Company G, Marine Cryptologic Support Battalion, Menwith Hill, UK.

From August 2007 to November 2008, Col Schaefer was the S-2 officer at 3d Battalion, 4th Marines and graduated from MAGTF Intelligence Officers Course (MOS: 0202). Additionally, he deployed with 3d Battalion, 4th Marines to Iraq in support of Operation Iraqi Freedom as their S-2 officer. In November 2008, Col Schaefer assumed the duties as the S-2 officer for 7th Marine Regiment and from October 2009 to October 2010, he deployed with the Regiment to Afghanistan in support of Operation Enduring Freedom.

From December 2010 to April 2012, Col Schaefer was assigned to the Defense Intelligence Agency. From May 2012 to May 2014 Col Schaefer was a plans officer at Headquarters Marine Corps Intelligence Department.

From July 2015 to May 2017, Col Schaefer was the S-2 officer at the 22d Marine Expeditionary Unit and deployed with the MEU aboard the WASP Amphibious Readiness Group in 2016 supporting combat operations in Libya.

From June 2017 to June 2019, Col Schaefer commanded Marine Cryptologic Support Battalion.

From June 2020 to May 2022, Col Schaefer was assigned to U.S. Central Command J2 Directorate as a current operations branch chief. Also, during this time he deployed to Riyadh, Kingdom of Saudi Arabia as the J2 officer for U.S. Central Command Forward—Kingdom of Saudi Arabia.

From June 2022 to June 2023, Col Schaefer was the CJ2 Director at Combined Joint Task Force—Operation Inherent Resolve in Baghdad, Iraq.

In July 2023, Col Schaefer assumed command of Headquarters and Service Battalion, Marine Forces Pacific.

Col Schaefer is a distinguished graduate from the U.S. Army Command and General Staff College in Fort Leavenworth, Kansas, a superior graduate from the U.S. Army War College in Carlisle, PA, and recipient of the academic year 2020 Marine Corps Association and Foundation General Thomas Holcomb Writing Award. He holds a Master of Arts degree in Administrative Leadership from the University of Oklahoma, and a Master of Strategic Studies degree from the U.S. Army War College.