Thanksgiving, or Thanksgiving Day, is an annual one-day holiday to give thanks at the conclusion of the harvest season. The United States celebrates Thanksgiving on the fourth Thursday of November and Canada celebrates the holiday on the second Monday in October.

Canada
In Canada, Thanksgiving is a three-day weekend (although some provinces observe a four day weekend, Friday–Monday). Traditional Thanksgiving meals prominently feature turkey, stuffing, and mashed potatoes, though Canada's multicultural heritage has seen many families infuse this traditional meal with elements of their traditional ethnic foods. As a liturgical festival, the Canadian Thanksgiving corresponds to the European harvest festival, during which churches are adorned with cornucopias, pumpkins, corn, wheat sheaves and other harvest bounty. English and other European harvest hymns are customarily sung on the Sunday of Thanksgiving weekend, along with scriptural lections derived from biblical stories relating to the Jewish harvest festival of Sukkot. While the actual Thanksgiving holiday occurs on a Monday, Canadian families might eat their Thanksgiving meal on any day of the three day weekend. The holiday can also be a time for weekend getaways for couples to observe the autumn leaves, spend one last weekend at their summer homes, or participate in various outdoor activities such as hiking, fishing and hunting.

Traditional celebration
The history of Thanksgiving in Canada goes back to an English explorer, Martin Frobisher, who had been futilely attempting to find a northern passage to the Orient. He did, however, establish a settlement in Canada. In the year 1578, Frobisher held a formal ceremony in what is now the province of Newfoundland and Labrador, to give thanks for surviving the long journey. This event is widely considered to be the first Canadian Thanksgiving, and the first official Thanksgiving to occur in North America. More settlers arrived and continued the ceremonial tradition initiated by Frobisher, who was eventually knighted and had an inlet of the Atlantic Ocean in northern Canada named after him — Frobisher Bay.
It should be noted that the 1578 ceremony was not the first Thanksgiving as defined by Native American tradition. Long before the time of Martin Frobisher, it was traditional in many Native American cultures to offer an official giving of thanks during autumnal gatherings. In Haudenasonee culture, Thanksgiving is a prayer recited to honor "the three sisters" (i.e., beans, corn and squash) during the fall harvest.

History of Thanksgiving in Canada

Main article: Thanksgiving (United States) United States
In the United States, certain kinds of food are traditionally served at Thanksgiving meals. First and foremost, turkey is the featured item in most Thanksgiving feasts (so much so that Thanksgiving is sometimes called "Turkey Day"). Stuffing, mashed potatoes with gravy, sweet potatoes, cranberry sauce, corn, turnips, yams and pumpkin pie are commonly associated with Thanksgiving dinner. All of these dishes (except for yams) are native to the Americas, and were introduced as a new food source to the Europeans when they arrived.

Traditional celebration

The Virginia colony
The early settlers of Plymouth Colony in Massachusetts were particularly grateful to Squanto, the Native American who taught them how to catch eel, grow corn and who served as their native interpreter (as Squanto had learned English as a slave in Europe). Without Squanto's assistance, the settlers might not have survived in the New World.
The Plymouth settlers (who came to be called "Pilgrims") set apart a holiday immediately after their first harvest in 1621, when they held an autumn celebration of food, feasting, and praising God. The Native American chiefs Massassoit, Squanto and Samoset joined in the celebration with ninety of their men in the three-day event.
Modern Thanksgiving in the United States is celebrated on the fourth Thursday in November.

See also
Thanksgiving: An American Holiday, An American History, by Diana Karter Appelbaum