On Oct. 3, 1789, President George Washington felt compelled to issue a proclamation designating November 26 of that year as a national day of thanksgiving for U.S. citizens, to give thanks for their newly created nation and federal Constitution. In those days before social media and other fast communication, his method of getting the word out was having it published in newspapers throughout the country. He also sent a blanket distribution to the various governors, requesting that they announce and observe the day within their states. Public festivities were held and Washington himself celebrated the day by attending services at St. Paul's Chapel in New York City, and doing a bit of philanthropy - donating beer (!) and food to imprisoned debtors in the city.
But Washington's proclamation did not establish an annual specific “Thanksgiving Day,” although he did issue another proclamation in February 1795 to recognize the defeat of a taxation rebellion in Pennsylvania. Later on, other presidents also declared one-time days of thanksgiving, with no specific date attached.
That held until the Roosevelt era, when perhaps the first "Black Friday" dispute arose. On two separate years - 1933 and 1939, November had five Thursdays instead of four. As a result, retailers had less time to rein in shoppers during the period between Thanksgiving and Christmas. So in 1933 they asked President Franklin D. Roosevelt to move Thanksgiving up a week. He denied their request and Thanksgiving remained the last Thursday that year. Then when the same thing happened in 1939, they again proposed to have Thanksgiving a week earlier. The second time around, FDR gave in to the pressure and moved it up. However, a few governors kept the holiday on the last Thursday of the month in their states, so there were essentially two Thanksgivings for some folks that year. This division went on for more two years, with Roosevelt declaring the second-to-last Thursday as the official holiday, and some states sticking with the last Thursday of the month schedule. Finally on Dec. 26, 1941, Congress passed a law making Thanksgiving the fourth Thursday of November.
So that's why Thanksgiving seems so late this year ... and perhaps why sales keep getting earlier and earlier!