When the Pilgrims came to Plymouth in 1620 aboard the Mayflower, they had already agreed to abide by the "Mayflower Compact" signed while crossing the ocean and which obligated them to pass just and equal laws for the general good of the colony.
As Puritans, they also carried with them a deep and abiding faith in the Hebrew Bible, and believed that the laws in Leviticus were obligatory for them as well as for the Jews. It is no surprise, therefore, that after the hardships of that first, terrible winter where only 50 survived of the 110 who left England, that the then Governor, William Bradford, declared a day of Thanksgiving, saying "Our fathers cried unto Him and He heard their voice and looked on their adversity" (Deuteronomy 26:7). Knowledgeable of the Jewish scriptures, and considering themselves chosen like the Jews of old, they saw the Festival of Weeks (Sukkot) as a model on which to base their celebration of God's mercy.
Bradford could not believe his eyes when a Wampanoag Indian by the name of Samoset walked into their devastated camp in March of that terrible year and spoke an English which he had learned from British fishermen along the coast. He introduced the starving colonists to his friend Squanto, who spoke even better English after having lived in England for over 10 years. It was Squanto who actually taught them how to survive the bitter Massachusetts winter by growing corn, catching fish, and tapping maple syrup from the appropriate trees in time before the next onset of winter. As the spring progressed, the colonists recovered, and to thank God and the Indians for their help, Bradford declared a three day Thanksgiving holiday that Squanto, the local Wampanoag chief Massasoit, and 90 braves attended. In the spirit of the occasion, and understanding the dire straits of the colonists, they also brought most of their own food!
In the years that followed, the colonists took to celebrating Thanksgiving in the fall after the harvests, but did it on different days. It wasn't until Lincoln's "Thanksgiving Proclamation" in 1863, in the midst of a terrible Civil War, that the final Thursday of November was selected as a national day of Thanksgiving. Lincoln saw a resurgent North growing in prosperity and population even in the midst of this awful conflict, and thought it the result of Divine Providence: "They are the gracious gifts of the Most High God, who, while dealing with us in anger for our sins, hath nevertheless remembered mercy."
Lincoln further said, eloquent as always:" I do therefore invite my fellow-citizens in every part of the United States, and also those who are in foreign lands, to set apart and observe the last Thursday of November next as a day of thanksgiving and praise to our beneficent Father who dwelleth in the heavens... commend to His tender care all those who have become widows, orphans, mourners, or sufferers in the lamentable civil strife in which we are unavoidably engaged, and fervently implore the imposition of the Almighty hand to heal the wounds of the nation and to restore it, as soon as may be consistent with the divine purpose, to the full enjoyment of peace, harmony, tranquillity, and union."
Today we continue to celebrate Thanksgiving on the last Thursday of the month, and though it has become a more secular holiday in actual practice, we should still take some time out in its course to thank God for all that we have.