Sergeant Major Delwin K. Ellington enlisted in the Marine Corps on 11 May 1998. He attended Recruit Training at MCRD Parris Island, South Carolina. Following his graduation, he reported to Marine Corps Base Camp Lejeune, North Carolina for Marine Combat Training. Upon completion, he reported to Assault Amphibian School Battalion at Camp Pendleton, California and acquired the MOS 1833, Amphibious Assault Crewman.

In December 1998, Sergeant Major Ellington reported to Headquarters and Service Company, 4th Assault Amphibian Battalion in Tampa Florida where he served as both AAV and Training NCO.

In January 2002, Sergeant Major Ellington received orders to 3rd Assault Amphibian Battalion at Camp Pendleton, California where he was assigned to Headquarters and Service Company as a Section Leader. In February 2003, he deployed in support of “Operation Iraqi Freedom.” After his return from Iraq, he was reassigned to Company C where he deployed twice to Okinawa, Japan. During the first deployment he served as Section Leader and participated in various training exercises which include operations at Camp Fuji. During his second deployment to Japan, he was attached to the 31st Marine Expeditionary Unit, Battalion Landing Team 1/3, where he participated in “Operation Phantom Fury” in Fallujah, Iraq.

In December 2005, Sergeant Major Ellington graduated Drill Instructor School at MCRD San Diego and was subsequently assigned to Company K, 3rd Recruit Training Battalion where he served as Drill Instructor, Senior Drill Instructor, Chief Drill Instructor, and Battalion Drill Master. During his tour in the Drill Field, Sergeant Major Ellington was meritoriously promoted to the rank Gunnery Sergeant.

In January 2009 Sergeant Major Ellington received orders to Combat Assault Company, 3rd Marine Regiment at Kaneohe Bay, Hawaii where he served as AAV Platoon Sergeant, Company GySgt, Company First Sergeant, and AAV Platoon Commander.

In December 2010, Sergeant Major Ellington was selected to the rank of First Sergeant and reported for duty to Battery A, 1st Battalion, 12th Marines at Kaneohe Bay, Hawaii. While assigned to Battery A, he deployed to Afghanistan in support of “Operation Enduring Freedom.”

In May 2012, Sergeant Major Ellington received orders to 7th Engineer Support Battalion, 1st Marine Logistics Group at Camp Pendleton, California, where he served as Company First Sergeant for both Company B and Explosive Ordnance Disposal Company.

In April 2014, Sergeant Major Ellington received orders to Headquarters and Service Company 2d Battalion, 23d Marines at Pasadena, California where he served as the Inspector-Instructor First Sergeant for Headquarters and Service Company.
In January 2016, Sergeant Major Ellington was frocked to his current rank and was ordered to report to Marine All Weather Fighter Attack Squadron 225, Miramar California. While assigned to VMFA(AW)-225, he deployed as a part of Unit Deployment Program 2016.

In January of 2018 Sergeant Major Ellington received orders to Marine Wing Headquarters Squadron-3, Miramar California.
In March of 2019 Sergeant Major Ellington received orders to his current post as the Command Element Sergeant Major for Special Purpose MAGTF-Crisis Response-Central Command 19.2.

Sergeant Major Ellington’s personal decoration include the Meritorious Service Medal, Navy Commendation Medal with 4 gold star in lieu of 5th award with valor device, Navy and Marine Corps Achievement Medal with 1 gold star in lieu of 2nd award, Combat Action Ribbon, and the Outstanding Volunteer Service Medal.