Sergeant Major Mario A. Castañeda was born in Tegucigalpa, Honduras. In 1996, he enlisted from Chicago, IL and attended recruit training at Marine Corps Recruit Depot, San Diego, CA. Upon completion of Enlisted Basic Supply Course, he was assigned to Supply Company, 3d Supply Battalion, 3d Force Service Support Group where he served as Fiscal Clerk.
He was transferred to Marine Expeditionary Unit Service Support Group 31 in June 1998, where he participated in operations SOUTHERN WATCH, SUDDEN STORM, DESERT FOX, and ANVIL II while deployed to the Arabian Gulf. In October 1999, he received orders to Marine Air Control Squadron 1, Marine Air Control Group 38, 3d Marine Aircraft Wing in Yuma Arizona.
In August 2001, he was transferred to Recruiting Station Albany at the Watervliet Arsenal, in Watervliet, NY and served as supply NCO. During that time, he had several collateral duties such as logistics NCO, Color Sergeant, burial detail, and volunteered to conduct military training for the American Legion Boy’s State and Notre Dame High School NJROTC mini-boot camp.
In July 2004, reported to Drill Instructor School, Marine Corps Recruit Depot, San Diego, CA. Upon completion of Drill Instructor School, he was assigned to Company B, 1st Recruit Training Battalion where he served as Drill Instructor, Senior Drill Instructor, and Series Chief Drill Instructor.
In May 2007, he was assigned as Supply Chief, 13th Marine Expeditionary Unit, Camp Pendleton, CA. During that time he deployed to Iraq in support of Operation IRAQI FREEDOM and he also deployed aboard the USS Boxer in support of Western Pacific Float 91.
In September 2009, He was transferred to Detachment West, Marine Special Operations Support Group, Marine Special Operations Command to serve as Supply Chief. In that capacity, he deployed to Afghanistan in support of Operation ENDURING FREEDOM with Special Operations Task Force 81 and served in additional roles as Company Gunnery Sergeant and Company First Sergeant, and was subsequently selected to First Sergeant in 2012.
He was assigned as Inspector Instructor First Sergeant for Site Support, Erie, PA in February 2012. In 2015, he reported to 3d Battalion, 1st Marines, 1st Marine Division for service as Company First Sergeant, Company K and deployed in support of Forward Deployed BN West and was selected to the rank of Sergeant Major in 2017 and was assigned as Sergeant Major of Marine Aerial Refueler Transport Squadron 352.
In July 2019, he assumed his current duties as Sergeant Major of 1st Light Armored Reconnaissance Battalion.
Sergeant Major Castañeda’s personal awards include the Meritorious Service Medal with Gold Star, Navy and Marine Corps Commendation Medal with Gold Star, Navy and Marine Corps Achievement Medal with Gold Star, Army Achievement Medal, and the Military Outstanding Volunteer Service Medal.