Lincoln’s Thanksgiving, And Ours:

'How Abraham Lincoln created Thanksgiving.'

Allen C. Guelzo The American Mind.

"November thanksgivings, as local holidays, had been in place for decades before Abraham Lincoln was elected as the sixteenth president in November 1860. ...

"And though Lincoln was descended from the first generation of New Englanders, the back-story of how Thanksgiving became a national holiday has a wider scope than simple genealogy—or even the simple giving of thanks. ..."

See Lincoln, "The Gettysburg Address", Gateway to the Great Books (10 Vol., 1963) volume 6;
We Hold These Truths: Understanding the Ideas and Ideals of the Constitution, by Mortimer J. Adler, p. 194.