William Mullins is believed to have been a shoemaker, based on the contents of his estate. He sailed on the Mayflower with his wife Alice, daughter Priscilla, son Joseph, and servant Robert Carter.

All of William's family died during the first winter, except his daughter Priscilla, who later married fellow passenger John Alden and had a large family.  William Mullins's eldest son, also named William, came to America later and arrived in Duxbury by 1637. This son had one daughter, but she had no children.