Sergeant Major Brian S. Alsleben enlisted in the Marine Corps on 10 January 1989.
Pvt. Alsleben reported to Heavy Equipment School at Court House Bay, Camp Lejeune North Carolina. In October 1990, LCpl Alsleben received orders to 1st FSSG, Camp Pendleton, California and was attached to the 1st FSSG, 7th Engineer Support Battalion. In January 1991 Lance Corporal Alsleben was deployed with 7th Engineer Support Battalion in support of Operation Desert Storm and Desert Shield.
In April 1995 Lance Corporal Alsleben was placed back on active duty and received orders to NAS Memphis, Tennessee for basic aviation school.
In February 1999 Sergeant Alsleben deployed with Heavy Medium Marine Squadron 162 and participated in operation Kosovo.
In 2002 Staff Sergeant Alsleben received orders to MCRD Parris Island to earn the MOS 8511/Drill Instructor. On July 2002 Staff Sergeant Alsleben successfully graduated Drill Instructor School and received orders to 1st Recruit Training Battalion, Delta Company.
From January of 2007 to January 2008 Gunnery Sergeant Alsleben was deployed to Iraq and participated in Operation Iraqi Freedom and Operation Enduring Freedom with Marine Aviation Logistics Squadron 29.
In March 2009 Gunnery Sergeant Alsleben deployed to Afghanistan with Marine Aviation Logistics Squadron. Gunnery Sergeant Alsleben participated in Operation Khan Jar and Operation Mosh Tarak.
On 1 April, 2009 GySgt Alsleben was promoted to 1st Sergeant and received orders to 3rd Battalion, Marine Recruit Depot, Parris Island South Carolina.
In May of 2013 1stSgt Alsleben received orders to Officer Candidate School, Quantico VA for Summer Officer Candidate training. 1stSgt Alsleben was assigned as to India Company 1stsgt for two increments of Officer Candidate training.
In February of 2014 1stSgt Alsleben was promoted to SgtMaj and transferred to 1sts Battalion, 8th Marines to serve as battalion SgtMaj. In December 2016 SgtMaj Alsleben was transferred to HMH-464 to serve as the squadron Sergeant Major.
His personal awards and decorations include the Navy/Marine Corps Commendation Medal with one gold star and the Navy/Marine Corps Achievement Medal with two gold stars, Good Conduct Medal with Silver Star/Bronze Star.