In 1939, FDR decided to move Thanksgiving Day forward by a week. Rather than take place on its traditional date, the last Thursday of November, he decreed that the annual holiday would instead be celebrated a week earlier.

The reason was economic. There were five Thursdays in November that year, which meant that Thanksgiving would fall on the 30th. That left just 20 shopping days till Christmas. By moving the holiday up a week to Nov. 23, the president hoped to give the economy a lift by allowing shoppers more time to make their purchases and—so his theory went—spend more money.

 The plan did not turn out too well:

For the next two years, Roosevelt continued to move up the date of Thanksgiving, and more states resigned themselves to celebrating early. By 1941, however, the facts turned against Roosevelt.

By then, retailers had two years of experience with the early Thanksgiving, and data were available regarding the 1939 and 1940 Christmas shopping seasons. In mid-March 1941, The Wall Street Journal reported the results of a survey done in New York City. The Journal's headline put it succinctly: "Early Thanksgiving Not Worth Extra Turkey or Doll." Only 37% of stores surveyed favored the early date. In Washington, the federal government reported that the early Thanksgiving resulted in no boost to retail sales.

And so, on May 20, 1941, FDR called a press conference at the White House and announced that he was changing Thanksgiving Day back to its traditional date. The early Thanksgiving had been an "experiment," he said, and the experiment failed. It was too late to move the 1941 Thanksgiving back to the traditional date, but in 1942 Thanksgiving would revert to the last Thursday of the month. This was "the first time any New Deal experiment was voluntarily abandoned," a Washington Post columnist wrote.

Apparently during the debate over whether to honor the Roosevelt's wishes,

People started referring to Nov. 30 as the "Republican Thanksgiving" and Nov. 23 as the "Democratic Thanksgiving" or "Franksgiving."