The Borg were first found by the Star Ship Enterprise, commanded by Jean-Luc Picard. Jean-Luc was soon thereafter taken hostage aboard the Borg's giant cube, then assimilated. The Borg traveled toward sector 001, our solar system, and the famous battle of Wolf 359, where numerous Star Ships and crew gave their lives. Picard's first officer took command and rescued the newly assimilated Locutus of Borg, and Federation science took care of the rest, restoring everything to normal about the famed captain, except a mental link, that proved useful in times to come. Years later, the captain still experienced traumatic nightmares about his experience with the Borg and was overtaken with revenge when the Borg returned to Earth and traveled through time to stop First Contact [M: F.C.]

These cyborgs' headquarters is in the Delta Quadrant - the same one that the Star Ship Voyager was swept to by a sentient life form named the "Caretaker". In this particular quadrant, Voyager and her crew came upon many Borg, including Seven of Nine, a Borg turned Federation officer, by the EMH [Emergency Medical Hologram] aboard the Star Ship. The EMH did a complex surgery on Seven of Nine, only performed once before, on Locutus of the Borg, or, Picard.