Thanksgiving是英国基督教的一个习俗，早于五月花的Virginia Jamestown就有庆祝，而且也不一定是秋收以后。五月花的Thanksgiving被赋予了过多的神话色彩。哄小孩可以，但是成年人不要以讹传讹。
https://en.wikipedia.org/wiki/Thanksgiving#In_the_United_States
The annual Thanksgiving holiday tradition in the United States is documented for the first time in 1619, in what is now called the Commonwealth of Virginia. Thirty-eight English settlers aboard the ship Margaret arrived by way of the James River at Berkeley Hundred in Charles City County, Virginia on December 4, 1619. The landing was immediately followed by a religious celebration, specifically dictated by the group's charter from the London Company.
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The more familiar Thanksgiving precedent is traced to the Pilgrims and Puritans who emigrated from England in the 1620s and 1630s. They brought their previous tradition of Days of Fasting and Days of Thanksgiving with them to New England. The 1621 Plymouth, Massachusetts thanksgiving was prompted by a good harvest.
