Every year on the fourth Thursday in November, families across the country gather together to celebrate Thanksgiving. The roots of the holiday trace back to 1621 to give thanks for a bountiful harvest in Plymouth, Massachusetts. Thanksgiving has been observed on various dates throughout its history. It became a national holiday in 1863 when Abraham Lincoln declared the last Thursday in November Thanksgiving. It wasn’t until 1941 however, that Thanksgiving was moved to the fourth Thursday in November to give the country an economic boost by giving people more time to shop before Christmas.