Emmett Scott
Emmett Scott was a tea merchant in Bristol, and the father to Caroline Scott. Through his daughter's marriage, he was the father-in-law of the pirate Edward Kenway and grandfather of Jennifer Scott.
Emmett's association to the Templars was made known to Edward Kenway by the family servant Rose, upon Edward's return to Bristol from the West Indies. It was from Rose that Kenway also learned that Emmett had caught smallpox, survived and transferred the disease to his wife and Caroline, which later caused Caroline's death.
These two factors led Kenway to plan Emmett's assassination, as a "tying up of loose ends", following which Edward devoted his efforts to the Assassins as a formal member, after accepting a pardon and offer of property from Robert Walpole.