Peter Ludlow was a Colonel in the United States Army who served in the Middle East before being assigned to Stargate Command, where he was initially appointed as the second in command to SG-14, though he later rose to command his own team; SG-25.
Born on the March 26 1969, in the city of Harrisburg, Pennsylvania, Ludlow had an unremarkable childhood and eventually trained as a carpenter so that he could enter his family's business. Although he became rather successful, Ludlow had always harbored a desire to enter the military and so, at the age of twenty two, he entered himself into the United States Air Force. While completing his basic training at the Lackland Air Force Base in Texas, Ludlow's obvious talents and leadership abilities were spotted by his superiors, who then recommended him to the Black Ops division.
Ludlow went on to do two more years of Special Operations training, which lasted approximately two years, before being deployed as part of a covert team in the Middle East. After surviving that mission, Ludlow went on to serve in numerous missions for ten years, specializing in the Middle East. However, in 1999, Ludlow was selected as a candidate for an SG team serving Stargate Command. After accepting the position, he was made 2IC of SG-14, where he presumably served until 2005 when he was given command of SG-25.
Because of his previous training, Ludlow's team often undertook undercover and stealth missions on other planets, though they were also adept at rescue missions and were often deployed in order to render assistance to other SG teams. (SG1: "The DVD Collection 78") On one of their undercover missions, to the planet designated P9J-333 by the Tau'ri, that Ludlow's team were given Sodan Invisibility devices and tasked with monitoring the Ori Prior who had been sent to convert to planet to Origin. While using the devices, they unwittingly unleashed an Interdimensional parasite from another dimension.
This bug mutated one of the planets local animals into a vicious beast which then attacked Ludlow and his team. Though they were all badly injured, Vala Mal Doran was able to use a Goa'uld healing device to heal their injuries and saved their lives. (SG1: "Uninvited") Teal'c later reported that it was unfortunate his superior abilities as a tactician had failed him when he was attacked by the beast, but that he looked forward to seeing Ludlow back in active duty. (SG1: "The DVD Collection 78")