History of Thanksgiving: How the Holiday Started in the 1600s and Evolved Into Today's Traditions

Two American airmen wait on their young British guests during a Thanksgiving party on November 27, 1942. H. F. Davis/Topical Press Agency/Getty

As soon as young Americans can say "Thanksgiving," they're learning about the origins of the holiday.

You probably know the legend yourself: The pilgrims came to North America from England in hopes of finding religious freedom and riches, but they struggled all winter. By November 1621, they'd finally grown some food, so they sat down for a three-day feast with members of the nearby Wampanoag tribe. Everyone was thankful, and an American tradition was born. The end.

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Except, that wasn't the end. Thanksgiving has evolved over the past couple of centuries, and researchers are constantly debating its history. (For example, were the Wampanoag at peace with the pilgrims or mad because the Englishmen robbed them?). In that sense, this Thursday's holiday is not just about turkey and football—it's also a chance to learn.

Here are five other facts about Thanksgivings past:

1. Though the so-called first Thanksgiving was in 1621, it wasn't until 1789 that George Washington set aside a national day of thanks. Abraham Lincoln issued a proclamation calling for a federal Thanksgiving holiday in 1861, writing that the country's gifts from God "should be solemnly, reverently and gratefully acknowledged as with one heart and one voice by the whole American people."

2. Franklin Roosevelt announced in 1939 that he was moving Thanksgiving in an effort to pump up holiday sales, but his decision proved unpopular with football coaches and retailers alike, according to Time. He ultimately set it for the fourth Thursday of every November.

3. The first Thanksgiving menu didn't have turkey or green bean casserole on it. Instead, participants likely ate corn, venison and wild birds, according to Smithsonian Magazine. Turkey became the centerpiece in the 1800s alongside foods like oyster soup, potatoes, mince pies, cranberry sauce and pumpkin pies. (Green bean casserole rose to fame in 1955, according to NBC News.)

4. Recent U.S. presidents have taken Thanksgiving as seriously as their predecessors did. Though the turkey pardoning legend dates back to Lincoln, the tradition picked up steam in 1963, when John F. Kennedy was presented with a bird and said "let's keep him going," according to the White House Historical Association. George H. W. Bush made the pardon official, and Barack Obama is to blame for the dad jokes.

5. The Macy's Thanksgiving Day Parade started in 1924 with floats, zoo animals, bands and about 10,000 spectators, but the event's signature balloons didn't join the fun until 1927, according to CNN. The most famous original balloon was Felix the Cat. The parade grew quickly: On Thursday, some 3 million people are expected to turn out to watch in New York City. Balloons will include SpongeBob Squarepants, Pikachu, the Pillsbury Dough Boy and Olaf from Frozen.

Now you know...so go eat.