and for having "been enabled to establish constitutions of government for our safety and happiness, and particularly the national One now lately instituted, for the civil and religious liberty with which we are blessed...".

The early settlers of Plymouth Colony in Massachusetts were particularly grateful to Squanto, the Native American and former British slave who taught them how to both catch eel and grow corn and also served as their native interpreter. Without Squanto's assistance, the settlers might not have survived in the New World.

The Plymouth settlers (who came to be called "Pilgrims") set apart a holiday immediately after their first harvest in 1621. They held an autumn celebration of food, feasting, and praising God. The Governor of Plymouth invited Grand Sachem Massasoit and the Wampanoag people to join them in the feast. Evidence to support that claim came from diaries of Plymouth. The settlers fed and entertained the Native Americans for three days, at which point some of the Native Americans went into the forest, killed 5 deer, and gave them to the Governor as a gift.

National Thanksgiving Proclamations proclaim thanks for God’s providence in the events of the nation and, as President Washington explained in his Thanksgiving Proclamation, “for the many signal favors of Almighty God” in the lives of the people.

As congress recognized the importance of Thanksgiving observance, President George Washington issued a national Thanksgiving Proclamation in 1789. He wrote, "Now therefore I do recommend and assign Thursday the 26th day of November next to be devoted by the People of these States to the service of that great and glorious Being, who is the beneficent Author of all the good that was, that is, or that will be—That we may then all unite in rendering unto him our sincere and humble thanks—for his kind care and protection of the People of this Country...for the signal and manifold mercies, and the favorable interpositions of his Providence which we experienced in the tranquility, union, and plenty, which we have since enjoyed...and also that we may then unite in most humbly offering our prayers and supplications to the great Lord and Ruler of Nations and beseech him to pardon our national and other transgressions—to enable us all, whether in public or private stations, to perform our several and relative duties properly and punctually...To promote the knowledge and practice of true religion and virtue, and the increase of science among them and us—and generally to grant unto all Mankind such a degree of temporal prosperity as he alone knows to be best."

In 1789 Washington designated a national thanksgiving holiday for the newly ratified Constitution, specifically so that the people may thank God for "affording them an opportunity peaceably to establish a form of government for their safety and happiness" and for having "been enabled to establish constitutions of government for our safety and happiness, and particularly the national One now lately instituted, for the civil and religious liberty with which we are blessed... "

The first official Thanksgiving Proclamation made in America was issued by the Continental Congress in 1777. Six national Proclamations of Thanksgiving were issued in the first thirty years after the founding of the United States of America as an independent federation of States. President George Washington issued two, President John Adams issued two, President Thomas Jefferson made none and President James Madison issued two. After 1815 there were no more Thanksgiving Proclamations until the Presidency of Lincoln, who made two during the Civil War.

President Lincoln declared Thanksgiving a Federal holiday as a "prayerful day of Thanksgiving" on the last Thursday in November. Since then every U.S. President has always made an official Thanksgiving Proclamation on behalf of the nation. President Franklin D. Roosevelt set the date for Thanksgiving to the fourth Thursday of November in 1939 (approved by Congress in 1941).