Thanksgiving is observed on the second Monday in October. Canadians give thanks for a successful harvest, while the U.S. tradition remembers Pilgrims who settled in the United States.

Thanksgiving did not become an official holiday in Canada until 1957, when Parliament announced the day would be "a day of general thanksgiving to almighty God for the bountiful harvest with which Canada has been blessed."

Despite the rather late official proclamation, the first Thanksgiving Day in Canada after confederation was observed on April 15, 1872. It was a celebration of the recovery of the Prince of Wales (who later became King Edward VII) from a serious illness.

There is no record of a Thanksgiving Day between 1872 and 1879. Between 1879 and 1898, Thanksgiving was observed on a Thursday in November. In 1899, it was fixed on a Thursday in November. The Thanksgiving long weekend was born in 1908, when the holiday was fixed to a Monday in October.

In 1921, Parliament passed the Armistice Day Act, which stated that Thanksgiving would be observed on Armistice Day, which was fixed to Nov. 11.

Ten years later, Parliament adopted an amendment to the Act that the November 11 would be known as Remembrance Day, and Thanksgiving Day would fall on the second Monday of October.

Until Thanksgiving was became an official holiday in 1957, Parliament would announce the date of the holiday each year.

Source: Canadian Heritage, Government of Canada