There is of course much debate about when the first true Thanksgiving was. Was it in November of 1621, or was it just simply a spontaneous harvest festival?
The two ships were bringing much needed supplies to the colony as well as additional settlers. Supplies were running very low and when they heard that the ships would soon arrive they held a fast for several days and then a feast of Thanksgiving.
You may wonder how they knew that the ships were arriving. They had been spotted out to sea and a small craft brought the news to the colony. It took the ships a bit longer to arrive than anticipated and the feast was held before they arrived. Therefore, several of my ancestors were late for Thanksgiving.
Mary Becket later married George Soule who is my Mayflower ancestor.
Francis Sprague and his daughter Mercy Sprague were also my ancestors. Mercy later married William Tubbs.
Most likely the colonists were digging into the stores on the Anne that same day as they were really anticipating the supplies that were sent.