Victoria Day is a federal Canadian public holiday celebrated on the last Monday preceding May 25, in honour of Queen Victoria's birthday. As such, it is the Monday between the 18th to the 24th inclusive, and thus is always the penultimate Monday of May. The date is simultaneously that on which the current Canadian sovereign's official birthday is recognized. It is sometimes informally considered the beginning of the summer season in Canada.

The holiday has been observed in Canada since at least 1845, originally falling on Victoria's actual birthday (May 24, 1819). It continues to be celebrated in various fashions across the country; the holiday has always been a distinctly Canadian observance. Victoria Day is a federal statutory holiday, as well as a holiday in six of Canada's ten provinces and all three of its territories. In Quebec, before 2003, the Monday preceding 25 May of each year was unofficially the Fête de Dollard, a commemoration of Adam Dollard des Ormeaux initiated in the 1920s to coincide with Victoria Day. In 2003, provincial legislation officially created National Patriots' Day on the same date.

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