Because his personnel file is classified, much about his life prior to 2001 never came to surface. What is known is that he was born in the United States on November 4, 1955. Before the year 2000, he was reputedly recruited into the NID by Colonel Harold Maybourne. After Maybourne disappeared from the NID in 2000, following the exposure of his unauthorized off-world operations, Simmons took over many of his old duties within the NID. He would investigate several matters concerning the Stargate Program, particularly its flagship team, SG-1. He was despised by several members of Stargate Command, but unknown to them, the NID and The Pentagon, Simmons had his own agendas.