Sergeant Major Johnson enlisted in the Marine Corps in March 2002 in St. Louis, MO. He attended recruit training aboard Marine Corps Recruit Depot, San Diego, California, where he was meritoriously promoted to Private First Class upon graduation. After completing the School Of Infantry at Camp Pendleton, California to become 0311 riflemen, Private First Class Johnson received orders to 1st Battalion 7th Marines, 1st Marine Division, Twenty-nine Palms, and California. Private First Class Johnson deployed twice in support of Operation Iraqi Freedom, serving in billets of Rifleman through Squad leader. In August 2005, Corporal Johnson was meritoriously promoted to Sergeant.

From October 2005, Sergeant Johnson received orders to Tactical Training and Exercise Control Group, (TTECG) to serve as a coyote at the Urban Warfare Training Center . Sergeant served as a section leader and assistant operation chief.

In April 2008, Sergeant Johnson attended the Marine Combat Instructor School at Camp Geiger, NC. Upon graduation, Sergeant Johnson received orders to Alpha Company, Infantry Training Battalion. Sergeant Johnson served as a squad instructor and platoon commander. In 2009, Sergeant Johnson was promoted to Staff Sergeant and reassigned to Infantry Squad Leaders Course, Advanced Infantry Training Battalion serving as an instructor and Chief instructor.

In February 2012 Staff Sergeant Johnson received order to 1st Battalion 1st Marines, Camp Pendleton, California. Staff Sergeant deployed in support of Operation Enduring Freedom, the Diplomatic Security Mission in Sanaa, Yemen, and the Unit Deployment Program in Okinawa, Japan.. In August 2012, Staff Sergeant Johnson was meritoriously promoted to Gunnery Sergeant. Gunnery Sergeant served in the billets of platoon Sergeant and Company Gunnery Sergeant.

In July 2015, Gunnery Sergeant Johnson received orders to Weapons Training Battalion, Camp Lejeune NC. Gunnery Sergeant Johnson served as the Range Company First Sergeant. In February 2018, Gunnery Johnson was selected to First Sergeant.

In February 2018, Gunnery Sergeant Johnson was frocked to First Sergeant and received orders to 2d Marine Raider Battalion, Marine Forces, Special Operations Command, Camp Lejeune North Carolina. In July 2019 First Sergeant deployed with Marine Special Operations Company Golf in Support of Operation Inherent Resolve. First Sergeant Johnson served as Marine Special Operation Company Golf and Headquarters & Service Company First Sergeant.

In July 2020, First Sergeant Johnson received order to 2nd Battalion 10th Marines. First Sergeant Johnson served as the Kilo Battery First Sergeant. First Sergeant Johnson was selected to Sergeant Major in November 2021.

In January 2022, Sergeant Major Johnson received orders to Instructor-Inspector duty, 3d Battalion 23d Marines in Bridgeton, Missouri where he is currently serving as the Inspector and Instructor Sergeant Major.

Sergeant Major Johnson’s Personal Awards include: The Meritorious Service Medal, Navy and Marine Corps Commendation Medal with three gold stars in lieu of fourth award, and the Navy and Marine Corps Achievement Medal with gold star in lieu of second award, and Combat Action Ribbon with gold star in lieu of second award.