Born in Portsmouth, Virginia on the 10th of May 1970, Barber knew that he wanted to serve his country from a young age and so, at the age of eighteen, he joined the United States Marine Corps. After entering the Marine Corps School at Quantico, Virginia, Barber received Standard US Air Force technical training in the use of several weapons, including the Colt M16A3 rifle, M9 pistol, as well as the M249 Squad Automatic Weapon. In addition to this, Barber was also trained to use the Shoulder-Launched Multipurpose Assault Weapon, becoming an expert in its use. After graduating, Barber served in tours of the Gulf, Somalia, and Kosovo as part of Operation Allied Force between March and June of 1999 where he showed outstanding leadership potential. During these missions, Barber was know to use the rocket launcher he had been trained to use to destroy fortifications and bunkers, as well as tanks.
Due to his skills in these tours, Barber came to the attention of his commanding officers and became a potential recruit for Stargate Command. As such, Barber entered into an SGC trainee group where he demonstrated that he was more than capable of dealing with the unique demands that were likely to arise as part of an SG team. Thanks to this performance, he was indeed recruited into the SGC by Major General George S. Hammond later in 1999. There, Barber was assigned to the military combat team of SG-5 who acted as support to medical, scientific, archaeological, and diplomatic units on their off-world missions. Barber quickly adapted to life in his team, and Hammond considered him to certainly be a future team leader. (SG1: "The DVD Collection 28")
One of Barber's missions with SG-5 saw him sent to the planet P4X-347 where they came across a Goa'uld Pleasure Palace containing a strange light. Indeed, Barber soon became addicted to the light and so, upon returning to Earth, he became first depressed then suicidal due to withdrawal symptoms. As such, when Dr. Daniel Jackson returned from P4X-347, Barber ran into the unstable vortex formed by the incoming Stargate thus ending his life. Though at first the members of the SGC were shocked and confused by his actions, they later discovered the cause as the rest of SG-5 and SG-1 suffered from the same effects. (SG1: "The Light")