NEW YORK (AP) -- President George Washington's 1789 proclamation establishing the first federal Day of Thanksgiving is slated to be auctioned in New York City.
Christie's is auctioning it Nov. 14. The auction house estimates it will sell for $8 million to $12 million. It's being sold by a private American collector.
The proclamation established the first national Day of Thanksgiving on Nov. 26, 1789, and the first under the Constitution.
But the holiday wasn't nationalized or standardized until 1863, when it began a permanent federal holiday on the fourth Thursday in November. In 1939, it was moved to the third Thursday in November, and two years later, it went back to the fourth Thursday in November.
Christie's says the only other known copy of Washington's proclamation is at the Library of Congress.
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