After the American Revolution the first national Thanksgiving Day, proclaimed by President George Washington, was Nov. 26, 1789, and the Episcopal Church began celebrating an annual day of thanksgiving on the first Thursday in November. Some states established an annual Thanksgiving Day, but there was no annual national holiday until President Abraham Lincoln, urged by Sarah J. Hale, proclaimed one in 1863, appointing as the date the last Thursday of November. Although the only known contemporary account of the 1621 Plymouth harvest celebration had been rediscovered in 1841, the national Thanksgiving Day initially was not officially linked to it.

In 1939, 1940, and 1941 President Franklin D. Roosevelt proclaimed Thanksgiving the next-to-last Thursday in November. Conflicts arose between Roosevelt's proclamation and about half of those of state governors, and in 1941 Congress passed a joint resolution decreeing that Thanksgiving should fall on the fourth Thursday of November. The day is observed by church services and family reunions; the customary turkey dinner is a reminder of the wildfowl served at the Pilgrims' celebration. Canadians also celebrate a national Thanksgiving Day, on the second Monday in October; prior to 1957 it was on the last Monday of the month.