The national Thanksgiving holiday was set as the fourth Thursday in November by Congress on Oct. 6, 1941. The bill was signed into law by President Franklin D. Roosevelt on Dec. 26, 1941.
The history of a national day of Thanksgiving goes back to 1789 when President Washington declared that Nov. 26 would be a day set aside for thanks. Throughout the years, other presidents declared various days to be set aside for Thanksgiving, but there was no consistency to the date. In 1863, President Lincoln established the first regular national Thanksgiving holiday to occur on the last Thursday in November each year. In the early 20th century, not all states celebrated Thanksgiving according to Lincoln's proclamation. In 1941, Congress stepped in to establish an official date so that all states would celebrate at the same time.