Though the feast held in 1621 may be better remembered, the first official national Thanksgiving in the US was declared in 1789. On that day, Washington, the president at the time, offered thanks for "the great degree of tranquility, union, and plenty" following the revolution. Thanksgiving feasts were declared sporadically until 1863, when President Lincoln established it as a lasting holiday. Traditionally, the president pardons a live turkey each year. Why have recent presidents pardoned two? Discuss (http://forum.thefreedictionary.com/postst29775_George-Washington-Creates-Thanksgiving-Day--1789-.aspx)
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