William Bishop was born as a werepanther (Balam Tribe of the Bastet) on Wilke's Star in 2240. His family had lived in uninhabited forests and mountains on the planet for generations. Unlike the werewolves that lived in the cities and fought the Sabbat and other vampires, his forefathers kept to themselves and lived off the land. Eventually, the vampires succeeded in wiping out the majority of werewolves on the planet, however for some mysterious reason they did not eliminate William's forefathers. It is believed that the vampires did not see the point like a farmer that does not hunt a mountain lion that never ventures out of the forests and hills to kill his livestock. On top of that, the vampires had more pressing issues on their minds that were more important then going hundreds of miles into the forest to hunt down some harmless panthers.
Nevertheless, the vampires did recognize the presence of the werepanthers. Eventually, an agreement was made between them. A mini covenant. In exchange for the vampires allowing the werepanthers to live on Wilke's Star, the werepanthers would not attack or kill any of the vampires under any condition.
William's father, Eric Bishop, died in 2248 when he was eight years old and left behind a mysterious magical two sword set, which had been in their family for over a century, and donated the rest of his earnings to the Fraternal Order of Retired Tech Infantry Soldiers. Immediately following his father's death, William moved to Calaunt and shortly later joined a gang of wererats led by Bree Colby. William found that he had a natural gift of being able to use the swords his father had left behind and over the years. Mainly by training for thousands of hours, shear raw talent, and amazing instict he perfected their use to the point where the swords to him were like natural extentions of his arms. Along with that, William was able to adapt the hunting techniques he had learned as a young boy in the forests to the dangerous urban streets. By the time he was ten years old, he was an assassin for Colby and eliminated some of her most dangerous rivals that were both wererat and werewolf.
Along the way, William was aware that he was being watched and observed by vampires that were members of the Sabbat. He had witnessed their acts of murder and terror, but was never repulsed by such atrocities. To him, they were simply predators like him, but with a different style. He actually developed a respect for them. However on one fateful night in 2255, Bishop became curious and had a strong desire to face one in combat. He attacked and killed a member of the Sabbat. Soon after, he was hunted down and captured by the Sabbat. They questioned why he would break the covenant that had been in effect for nearly two centuries, before deciding whether or not to kill him. They learned that William's father had died before he could tell his son about that agreement. Someone high up in the Sabbat either took pity -- or saw a way to use this situation to his advantage -- and decided to allow William to live. William was then tortured for seven days (but not mutilated or otherwise permanently scarred) as punishment, but eventually released.
William remained on Wilke's Star until 2257 when he joined the Raptors. He was recruited by Major Bernard Dent who offered the position in exchange for helping him hunt down gifted draft dodgers on Wilke's Star that had evaded capture for years. After Bishop joined the Raptors, they were very successful on that planet.
After Bishop completed an assignment for Dent on Ashdown along with Michelle Fisher, who was another member of his unit, they both learned that they had a shared disatisfaction for the Federation. Later they were contacted by a member of the Sabbat, they expressed their desire to become involved. Apparently, someone high within the Sabbat was informed, and they were provided an opportunity to show their quality. They were provided the task of assassinating Aisha Ramirez, and they succeeded.
After killing Aisha Ramirez, William Bishop and Michelle Fisher were placed on leave and sent to Wilke's Star by Herbert Gergenstein and George Smits. When provided the opportunity to join the Sabbat, Fisher refused to follow through with a test of loyalty. Bishop killed her. Shortly after he was officially accepted into the Sabbat as a Templar answering to Santino. He also made contact and had a relationship with Melissa Cortona, another highly respected Sabbat member.
The Sabbat agreed to terms with the major tribe of wererats on Wilke's Star. In exchange for the assistance of the wererats as a front for a Sabbat take over of Van Diemen during the chaos of the Holy Terran Empire's war with the Earth Federation, the Wererats on Wilke's Star would be provided a significantly larger share of the black markets on Wilkes Star and Van Diemen, plus new rules of engagement so that they would no longer be at least openly hunted by the members of the Sabbat.
During the first phase of the operation led by Santino, the wererats and Sabbat members sought to eliminate all remaining and existing opposition to the wererats (and themselves) on Wilke's Star. During this operation Bishop and Melissa discovered and killed a powerful vampire that was a member of the Giovanni clan of vampires.
Afterwords they were sent to Van Diemen along with a large number of Sabbat members and wererats to cause a rebellion that ultimately result in John Tyler becoming leader of the planet who would largely answer to the Sabbat and not report their existence to higher authorities. Bishop and Cortona were sent on missions during which they uncovered a plot by a key member with the Sabbat (Malikait) and Claudius Giovanni to kill Santino and eventually attempt to overthrow Mordred himself.
Along with the assistance of Luther Petridis and a wraith called Hugh Montgomery, they were able to defeat Malikait and Claudius Giovanni, but not before they could prevent him from killing Santino. Afterwords, Bishop and Cortona were sent to Avalon by Mordred with orders to kill Vin Dane and retrieve the Orb.
During the mission Cortona was killed by Marshal Demar Palencia, who in turn was killed by Bishop. After the mission, Bishop murdered Irene York during a fit of anger. However, Fabian Cortez was killed on the mission as well. Shortly afterwords Bishop succeeded Fabian Cortez' position as Mordred's personal Templar.