Thanksgiving was one of those holidays people celebrated but not necessarily one that everyone recognized. Actually, it was a jumble of days with no rhyme or reason celebrated from state to state whenever.
That all changed when poet and editor Sarah J. Hale began lobbying for a national Thanksgiving holiday. During the Civil War, President Abraham Lincoln, looking for ways to unite the nation, discussed the subject with her. So in 1863, he gave his Thanksgiving Proclamation, declaring the last Thursday in November a day of thanksgiving.
During The Great Depression (specifically 1939-1941), FDR sought to lengthen the Christmas shopping season, and proclaimed Thanksgiving the 3rd Thursday in November. Controversy followed, and Congress passed a joint resolution in 1941 decreeing that Thanksgiving should fall on the fourth Thursday of November, where it remains.
Today's Black Friday, the 'traditional' start of the Christmas season. But if you've seen anything in the stores since, oh, August, you know that's a bunch of bologna. Still I know people who actually woke up at 4 this fine morning to brave the cold and people and do some shopping. Personally, forget it - I refuse to do that to myself. I'd rather pay full price than deal with all those people.