Born in England
, probably in Leyden, England
of unknown parentage, he may have been related to John Allerton
. He married Mary Norris
the same day his sister Sarah Allerton
married Degory Priest
Isaac Allerton, Mary Norris and their children Bartholomew, Remember and Mary were passengers on the Mayflower.
Isaac Allerton has a relatively small number of descendants, but these include Zachary Taylor and Franklin D. Roosevelt.