At least one line is well documented back to the immigrant ancestor, Willem Garritsen & Mary(?)
-Descendants were initially named Willemsen, later changing to Williamson

We thought we should have a place where ALL Williamsons could compare their Y-chromosome DNA.

To avoid duplication with the FTDNA Williams Surname Project, members with the surname Williams will need to have at least one Y-Match with a member of surname Williamson or Williamsen.