thanksgiving is a holiday celebrated in much of north america, generally observed as an expression of gratitude, usually to god. the most common view of its origin is that it was to give thanks to god for the bounty of the autumn harvest. in the united states, the holiday is celebrated on the fourth thursday in november. in canada, where the harvest generally ends earlier in the year, the holiday is celebrated on the second monday in october, which is observed as columbus day or protested as indigenous peoples day in the united states.