We hear often about the “War on Christmas,” but the Washington Post describes Thanksgiving as “the most politicized American holiday of the 19th century.” We can thank our Unitarian and Universalist forebears for some of that (sincerely). Many of them were abolitionists, and though there was not yet an agreed upon national day of thanksgiving, these abolitionist preachers would use local thanksgiving events to preach fiery sermons denouncing slavery.

But it was Unitarian Sarah Hale who really was the driving force behind what we now know of us Thanksgiving. (Side-note: the problematic and ahistorical myth of “the first Thanksgiving” between the Pilgrims and the Wampanoag wasn’t really associated with Thanksgiving until about 1900.)

Sarah was a powerful force in her day. Born in 1788, she was a widow with 5 children to support by the time she was 34, driving her to turn to her talents as a writer. She would also become an abolitionist, a public health advocate, a promoter of American writers, editor of the top women’s magazine, “Godey’s Lady’s Book,” and she helped to found Vassar college.

She also wrote “Mary Had a Little Lamb.”

She was passionate about the idea of a national day of Thanksgiving, feeling it resembled both the Christian feast of Pentecost and the Jewish days of thanksgiving. Sarah wanted a “universal day” for all religions to express gratitude. So she began writing to every president who came into office. President Zachary Taylor. President Millard Fillmore. President Franklin Pierce. President James Buchanan.

None responded to her.

Finally, at age 74, she wrote to President Lincoln. Shortly after, he issued a proclamation:

Happy Thanksgiving!