Sergeant Major Blackwell was born in McAlester, Oklahoma. He enlisted in the Marine Corps August 1999 and attended recruit training at Marine Corps Recruit Depot, Parris Island, SC, where he was meritoriously promoted to the rank of Private First Class. Upon graduation, he reported to Marine Corps Base, Camp Lejeune, NC, for Marine Combat Training. Upon completion, he reported to Marine Corps Communications Electronics School, Marine Corps Air Ground Combat Center, 29 Palms, CA, where he received the MOS of 2811.

In 2000, Sergeant Major Blackwell received orders to Headquarters and Service Battalion, Parris Island, SC. Upon completion of his tour in 2003, he was assigned to the 7th Communications Battalion, Okinawa, Japan. In January 2005, Sergeant Major Blackwell was deployed to support Combined Support Force-536 where he served as the Company Bravo Maintenance Chief in support of Operation Unified Assistance.

In 2006, Sergeant Major Blackwell attended Recruiters School at Marine Corps Recruit Depot, San Diego, CA. He was then assigned to Recruiting Station Detroit where he served as a production recruiter for 22 months, Noncommissioned Officer in Charge for 14 months, and promoted to the rank of Staff Sergeant. 

In 2009, Sergeant Major Blackwell returned to the Marine Corps Communications Electronics School, Marine Corps Air Ground Combat Center, 29 Palms, CA, where he received the MOS of 2862.

In 2010, Sergeant Major Blackwell received orders to 1st Combat Engineer Battalion, Camp Pendleton, CA. While there he served as the Battalion Communications Maintenance Chief and Company Gunnery Sergeant while in support of Operation Enduring Freedom for campaigns 10.1, 10.2 and 12.1.

In 2013, Sergeant Major Blackwell received orders to 1st Maintenance Battalion, Camp Pendleton, CA, where he served as the Voice and Data Repair Chief. He was promoted to Gunnery Sergeant in 2013 and served as the Company Gunnery Sergeant from 2014 - 2015. In 2015, Sergeant Major Blackwell received orders to Marine Corps Installations-East G6 where he served as the Operations Chief.

In 2017, he was promoted to First Sergeant and received orders to 2nd Law Enforcement Battalion, 2nd Marine Headquarters Group, where he served as the Bravo Company First Sergeant. In 2018 Sergeant Major Blackwell reported to Headquarters Support Battalion, Marines Corps Base Camp Lejeune where he served as the Military Police Company First Sergeant. 

Sergeant Major Blackwell received orders in 2019 to 2d Combat Engineer Battalion where served as the Mobility Assault Company First Sergeant and was deployed in support of Operation Allies Welcome in 2021. In November 2022, Sergeant Major Blackwell was promoted to his current rank and appointed to as the Battalion Sergeant Major of 3d Battalion, 2d Marines.

Sergeant Major Blackwell's personal awards consist of the Navy and Marine Corps Commendation Medal with three gold stars in lieu of 4th award and Navy and the Marine Corps Achievement Medal.