By Jon Delano

PITTSBURGH (KDKA) – This Thursday is a uniquely American national holiday, but Thanksgiving wasn’t always celebrated nationwide.

How did this holiday become such an American tradition?

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KDKA’s Jon Delano says Thanksgiving has always been special for his family. His ninth great-grandfather, Philippe de Lannoy, arrived in Plymouth in late 1621 after the first Thanksgiving and has often wondered what he missed when 90 Native Americans and 52 Pilgrim survivors enjoyed the first harvest feast.

“There are two eyewitness accounts of that event which was a three-day harvest festival with lots of feasting and fellowship. But it wasn’t until two years later that the Pilgrims used the word Thanksgiving,” says Melanie Kirkpatrick, author of “Thanksgiving: The Holiday at the Heart of the American Experience.”

Kirkpatrick, who has written about the history of Thanksgiving, says the Pilgrims owed a great deal of thanks to the native Wampanoag Indians who taught them how to survive in those early years.

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“It does point the way, in my view, to the multi-cultural diverse people we’ve become 400 years later,” she says.

In fact, the first menu had food from both Pilgrims and Indians — turkey, venison, squash and corn but no mashed potatoes, cranberry sauce or pumpkin pie!

“No pumpkin pie. Even though they had pumpkin, they had no wheat to make pastry,” says Kirkpatrick.

For the first 200 years, Thanksgiving was not an annual national holiday, although President George Washington’s first executive proclamation was a call to thanksgiving.

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“From the Pilgrims until 1863 when Abraham Lincoln called a national Thanksgiving, Thanksgivings were celebrated separately, state by state, or community by community,” says Kirkpatrick.

Enter Sarah Josepha Hale.

Hale, a teacher who wrote “Mary Had a Little Lamb” and later became the editor of the most popular women’s magazine of the time, embraced Thanksgiving.

“She wanted it to become a national holiday, and she campaigned in the pages of her magazine to create national support,” says Kirkpatrick.

Hale’s mission was ignored by most presidents who thought only governors could declare a thanksgiving.

But President Lincoln listened to Hale, and after the battle of Gettysburg called for a national Thanksgiving Day.

“He was able to issue a proclamation that was profoundly hopeful in nature. It called on Americans to come together in one voice with one heart to celebrate a national Thanksgiving,” says Kirkpatrick.

Every president since Lincoln has done the same, and just in case they wouldn’t, Congress finally made it official in 1941, declaring the fourth Thursday of November to be a national holiday.

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This Thanksgiving is the 400th anniversary of the first one!