Everyone knows that 'Thanksgiving' is celebrated in the US on the
fourth Thursday of November. However, before 1939, Presidents declared
Thanksgiving to be on the last Thursday of November. It is switched because, it has to do with the economy, the great depression and Christmas
sales.
In 1939, November actually had 5 Thursdays, instead of the
more-common 4. Because many stores thought it in bad taste to advertise
Christmas goods before Thanksgiving, this meant that the Christmas shopping
season was going to be especially short that year. With the Great Depression
still in full swing, FDR thought it better to move Thanksgiving up a week and
give stores an extra week to have Christmas sales. It wasn't a move without controversy, many called it an
affront to President Lincoln (who was the first to declare Thanksgiving an
official holiday) but nevertheless, it remains until today.
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