In their early lives, Upton and his brother traveled to the West Indies together, establishing a smuggling ring on which to build their fortune. They also purchased a treasure map from a pirate in Nassau and each kept half, intending to fund their retirement with the treasure it led to.
At the same time, the brothers became involved with the Assassin Brotherhood and used a portion of their smuggling money to support the cause. They were later named dual heads of the Nassau bureau as the city grew to prominence.
However, the Travers' lives changed when a Chinese pirate named Jing Lang arrived in Nassau and Vance became smitten with her. Interested in recovering their treasure, Lang encouraged Vance to kill his brother and take the other half of the map so that they could run away together.
When Edward Kenway arrived in Nassau in search of a Templar key, Vance claimed that the smugglers in the area were being controlled by a Templar, when in reality they were led by Upton. Once Kenway came close to assassinating Upton, the former explained who he was, and the latter revealed Vance's treachery.
Upton wished to confront his brother about the map and prove that his own version of events was true. He also knew that thieves would attempt to take either half of the map if he and his brother were together, and so asked Kenway to tail him as a bodyguard. He then met with Vance and discussed the map while Kenway killed any thieves attempting to approach them.
Vance tried to convince Upton to use their map to find the treasure, so they could each have a portion and move up in society. Upton was reluctant, saying it was best to keep the treasure hidden for when they needed it most. He also pointed out that Lang was not suited for the domestic life, as well as voicing his suspicions that there was more to her than she claimed.
The two brothers argued heatedly, and Vance swore he would kill Upton and take his half of the map if he did not consent to give it up. Kenway tailed Vance and found out that he had already sent an assassin after Upton, and that Lang was a Templar.
Kenway saved Upton from the assassin and explained what he had learned. Devastated by his brother's betrayal, Upton drowned his sorrows at the local tavern, forcing Kenway to protect him in brawls and from authorities until he sobered up. The next morning, his head cleared, Upton resolved that his brother and Jing both needed to die for their actions. Kenway then offered to carry out the deed himself to recover the Templar key.
- In 2015, his name was on a list of known British Assassins used by the Templar Isabelle Ardant.
- Upton and Vance's Assassin Robes are identical to those worn by the students of Ah Tabai at Tulum, with a different color scheme.