“I do therefore invite my fellow-citizens … to set apart and observe the last Thursday of November next as a day of thanksgiving and praise to our beneficent Father who dwelleth in the heavens.”
Abraham Lincoln, from his Thanksgiving Day proclamation, October 3, 1863.  Read the original text of President Lincoln’s Thanksgving Proclamation at: grove.ufl.edu/~leo/lincoln2.html.

[In early July of 1863, there were some 50,000 American casualties at the Battle of Gettysburg, and President Lincoln traveled to the field of battle about four months later to deliver the “Gettysburg Address.” Deeply moved by the sacrifice of these soldiers, Lincoln first committed his life to Christ while walking among the graves there. He later explained: “When I left Springfield [to become President] I asked the people to pray for me. I was not a Christian when I buried my son, the severest trial of my life, I was not a Christian. But when I went to Gettysburg and saw the graves of thousands of our soldiers, I then and there consecrated myself to Christ.”]