Thanksgiving is a uniquely American tradition, a Heritage Foundation report explains:
Following a resolution of Congress, President George Washington proclaimed Thursday the 26th of November 1789 a day of “public thanksgiving and prayer” devoted 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.” Reflecting American religious practice, Presidents and Congresses from the beginning of the republic have from time to time designated days of fasting and thanksgiving (the Thanksgiving holiday we continue to celebrate in November was established by Abraham Lincoln during the Civil War and made into law by Congress in 1941).
In setting aside a day for Thanksgiving, Washington established a non-sectarian tone for these devotions and stressed political, moral, and intellectual blessings that make self-government possible, in addition to personal and national repentance. Although the First Amendment prevents Congress from establishing a religion or prohibiting its free exercise, Presidents, as well as Congress, have always recognized the American regard for sacred practices and beliefs. Thus, throughout American history, Presidents have offered non-sectarian prayers for the victory of the military and in the wake of catastrophes. Transcending passionate quarrels over the proper role of religion in politics, the Thanksgiving Proclamation reminds us how natural their relationship has been. While church and state are separate, religion and politics, in their American refinement, prop each other up.
From all of us at Heritage, best wishes for a safe and happy Thanksgiving.