The Pilgrim Thanksgiving was, at best, the 4th or 5th such event recorded.
A Thanksgiving feast seems to have been quite a logical thing for European people from every country to hold. My own research suggests that one individual who attended the St. Sauveur celebration also attended the Jamestown event, and later the Plymouth Plantation event.
He was an agent for a land sales company owned by King James and his associates.
where they had "dindon, casserole aux haricots verts, des petits pains, et pommes de terres avec de la sauce brune." Bon appetit!