After the disbandment of the Van der Linde gang, whereof he was a member, Bill Williamson went on to establish his own gang at some point between 1907 and 1911. The gang eventually rose to prominence in New Austin, gaining a reputation as the most dangerous gang left in the West. Williamson and his gang took over Fort Mercer in Río Bravo, the former domain of the Del Lobo Gang.
Events of Red Dead Redemption
In 1911, John Marston confronts Bill Williamson and his gang, which results in him being shot and wounded. He is saved when a young woman named Bonnie MacFarlane and a ranch hand named Amos come across him and take him to a doctor.
Bill and his gang later raid Ridgewood Farm, killing the men and raping the women who live there, leaving only a few survivors. Marston, Marshal Johnson and the deputies rescue the remaining survivors at Ridgewood Farm, and then chase Williamson to Mercer Station. A gunfight ensues, and although Williamson flees, the posse successfully apprehends Bill's second-in-command, Norman Deek.
After Deek's capture, a member of the Williamson Gang arrives at the sheriff's office in Armadillo, explaining that Bonnie MacFarlane has been captured and will be hanged if they don't bring Norman Deek to Tumbleweed for exchange. Marston accompanies Marshal Johnson and his deputies, who are all ambushed as soon as they enter the town. Deek is swiftly gunned down by the Williamson gang during the shootout, while Marston saves Bonnie from being hanged by the gang. At the end, the Williamson gang's presence is eliminated from Tumbleweed, but Bill is not found among the dead.
Marston later recruits seven people to help him assault Fort Mercer and the Williamson gang. They use a Trojan horse strategy, where West Dickens presents his elixir to the outlaws, only for John to be hiding inside the wagon with a Gatling Gun, which leads to the gang’s annihilation. Although the Williamson gang was eliminated, including the reinforcements that attempted to retake the fort, Williamson himself managed to escape to Mexico on the previous day with the help of Javier Escuella.
Marston later travels to Mexico in pursuit of Bill and Javier. Marston either kills or captures Javier, then kills Bill with the help of Abraham Reyes and his rebels after being betrayed by the Mexican Army.
After the Williamson gang had gone from Fort Mercer, the Mexican Banditos would eventually take over, with lots of stolen money; Marston can clear them out with the aid of Leon Galindo in his travels.
The assault on Fort Mercer spelled the end for the Williamson gang, having lost all of its members, its hideout and with its leader having gone into exile.
- Bill Williamson - founder and leader; killed by either John Marston or Abraham Reyes.
- Norman Deek - second-in-command; killed by fellow gang members during an attempted ambush on John Marston and Marshal Johnson.
- Outlaw on Horse - killed by John Marston during the assault on Fort Mercer.
- Seth Briars (formerly)
- Harry Dobbing - can be killed or captured by Marston.
- Irvin Pennick - can be killed or captured by Marston.
- Rufus Starkley - can be killed or captured by Marston.
- Elmore Vinnis - can be killed by Marston.
- Kent Gallaway - can be killed or captured by Marston.
- Melvin Spinney - can be killed or captured by Marston.
- Ralph Stricker - can be killed or captured by Marston.
- Sid Winkler - can be killed or captured by Marston.
- Quinn Malloy - can be killed or captured by Marston.
- Zebedee Nash - can be killed or captured by Marston.
- Red Dead Redemption
- "Exodus in America"
- "Spare the Rod, Spoil the Bandit"
- "Hanging Bonnie MacFarlane"
- "The Assault on Fort Mercer"
- Aside from the above listed members, the Williamson gang is primarily made up of unaffiliated criminals. Many of the outlaws encountered alongside Williamson are also bounties, and two (Harry Dobbing, and Irvin Pennick) are listed as members of the Bollard Twins Gang or unaffiliated.
- Unlike most gangs, the Williamson gang doesn't offer the player an outfit, most likely because Bill’s gang doesn’t have a set uniform.
- It shares this trait with Dutch's Gang.
- In a random camp event in Red Dead Redemption 2, Bill Williamson mentions his desire to be the leader of his own gang one day, foreshadowing the creation of the Williamson gang.