As its prayerful name announces, Thanksgiving Day involves the bending of knees. To whom, after all, would celebrants give thanks if not to “Him”?Residents of Plymouth in the Massachusetts colony, headed by Gov. William Bradford, initiated the tradition in 1621, at least according to the conventional account. Historians have questioned whether Plymouth really was the site of the first Thanksgiving, whether the date is accurate, and whether early colonial events were not more akin to carnivals with feasts than holy days with formal services. Regardless of when, where or how they did so, the grateful didn’t thank goodness or luck; they thanked God.
Maybe this is just from my own experiences, but I have no problem with Thanksgiving and I've never seen in it as a religious holiday. I've always seen it as a celebration of religious freedom (which of course includes the freedom from it), and in my family it's always been celebrated as a sort of mini-family-reunion. Over the past several years, I've spent Thanksgiving with my wife's family, her sister and brother-in-law both being non-theist as well, and her parents are Anglican or some other protestant sect. There's never been any pre-dinner prayer thanking any invisible sky-daddies. We've always had a good time, outside of any family drama.