Thanksgiving, or Thanksgiving Day, celebrated on the fourth Thursday in November, at the end of the harvest season, is an annual American Federal holiday to express thanks for one's material and spiritual possessions. The period from Thanksgiving Day to New Year's Day often is called the holiday season. Most people celebrate by gathering at home with family or friends for a holiday feast. Read more about Thanksgiving

The first thanksgiving”, 1621the Pilgrims at Plymouth

  Squanto, a Patuxet Native American who resided with the Wampanoag tribe, taught the Pilgrims how to catch eel and grow corn and served as an interpreter for them (Squanto had learned English as a slave in Europe and travels in England). The Pilgrims set apart a day to celebrate at Plymouth immediately after their first harvest, in 1621. At the time, this was not regarded as a Thanksgiving observance; harvest festivals were existing parts of English and Wampanoag tradition alike. Several colonists have personal accounts of the 1621 feast in Plymouth, Massachusetts. There are 2 primary sources for the events of autumn 1621 in Plymouth : Edward Winslow writing in Mourt's Relation and William Bradford writing in Of Plymouth Plantation

"our harvest being gotten in, our governor sent four men on fowling, that so we might after a special manner rejoice together, after we had gathered the fruits of our labors; they four in one day killed as much fowl, as with a little help beside, served the Company almost a week, at which time amongst other Recreations, we exercised our Arms, many of the Indians coming amongst us, and amongst the rest their greatest king Massasoit, with some ninety men, whom for three days we entertained and feasted, and they went out and killed five Deer, which they brought to the Plantation and bestowed on our Governor, and upon the Captain and others. And although it be not always so plentiful, as it was at this time with us, yet by the goodness of God, we are so far from want, that we often wish you partakers of our plenty." -Edward Winslow, Mourt's Relation

  "They began now to gather in the small harvest they had, and to fit up their houses and dwellings against winter, being all well recovered in health and strength and had all things in good plenty. For as some were thus employed in affairs abroad, others were exercised in fishing, about cod and bass and other fish, of which they took good store, of which every family had their portion. All the summer there was no want; and now began to come in store of fowl, as winter approached, of which this place did abound when they came first (but afterward decreased by degrees). And besides waterfowl there was great store of wild turkeys, of which they took many, besides venison, etc. Besides, they had about a peck of meal a week to a person, or now since harvest, Indian corn to that proportion. Which made many afterwards write so largely of their plenty here to their friends in England, which were not feigned but true reports." -William Bradford, Of Plymouth Plantation more about Thanksgiving

During the American Revolutionary War the Continental Congress appointed one or more thanksgiving days each year, each time recommending to the executives of the various states the observance of these days in their states. The First National Proclamation of Thanksgiving was given by the Continental Congress in 1777.

  Sources:

-Thanksgiving (United States)

http://en.wikipedia.org/wiki/Thanksgiving_(United_States)

-Pilgrim Hall Museum

http://www.pilgrimhall.org/plgrmhll.htm

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