First Sergeant Wilmer Viera was born in Canovanas, Puerto Rico. He enlisted in the Marine Corps and attended recruit training in Kilo Company, 3rd Recruit Training Battalion, Marine Corps Recruit Depot, Parris Island, South Carolina in March 1998. He reported to Camp Beiger, North Carolina for Marine Combat Training. He was assigned to Fort Sill, Oklahoma for MOS school where he completed the Field Artillery Cannoneer Course and earned the MOS of 0811, Field Artillery. He was promoted to the rank of Private First Class while attending MOS School.
Upon completion of MOS school, Private First Class Viera reported for duty to Lima Battery, 3rd Battalion 10th Marines Regiment, Camp Lejeune, North Carolina in September 1998. During his tour, he deployed with BLT 3/8 in support of Kosovo Liberation Campaign, Operation Shining Hope. In April 1999 he was promoted to Lance Corporal. During the same period, he was meritoriously promoted to Corporal In June 2000. In January 2001, Viera was promoted to Sergeant.
Sergeant Viera then reported to Marine Security Forces Company, Kings Bay Georgia in June 2002 where he served as Sergeant of the Guard and Platoon Sergeant. In June 2005, Viera reported for duty to Headquarters Battery, Tenth Marines Regiment, Camp Lejeune, North Carolina. In September 2005, Viera reported to Tango Battery, 5th Battalion, 10th Marine Regiment, Camp Lejeune, North Carolina. During his tour, he was promoted to the rank of Staff Sergeant and deployed to Iraq in support of Operation Iraqi Freedom from March 2007 to October 2007 and from October 2008 to March 2009. He served as Artillery Platoon Sergeant and as Convoy Commander respectively.
In April 2010, Staff Sergeant Viera reported to Marine Corps Recruit Depot, Parris Island, South Carolina for Drill Instructor Duty. Upon completion of Drill Instructor school, he was assigned to the 1st Recruit Training Battalion Alpha Company. He was promoted to the rank of Gunnery Sergeant on 01 November 2011. Upon completion of his tour Viera received orders to 3rd Battalion 11th Marines, 29 Palms California. He served as Battery Gunnery Sergeant for Battery M and Headquarter Battery. During his tour with 11th Marines Gunnery Sergeant Viera deployed to Bahrain in support of Special Purpose MAGTF 15.1 and Security Cooperation Team 15.1 El Salvador in support of MARFORSOUTH.
Upon return from his tour in El Salvador in September 2015, Viera was promoted to his current rank of First Sergeant and received orders to 2D Battalion 7th Marines where he served as Company G, Company E, and Headquarters and Service Company First Sergeant.
In June 2018, First Sergeant Viera reported to Combat Logistics Battalion 15 to serve as Battalion Sergeant Major.
He has five daughters, Ruby, Vanessa, Astrid, Niurka, and Gabriella.
His personal awards include the Navy/Marine Corps Commendation Medal (with three gold stars), Navy and Marine Corps Achievement Medal (with two gold stars), and the Combat Action Ribbon.