直到1863年秋天，亚伯拉罕·林肯总统发布公告，宣布11月的最后一个星期四为全国感恩节，感恩节才成为美国的国定假日。

林肯发布公告时，将感恩节定为全国性节日的功劳应该归于莎拉·约瑟法·黑尔，她是《戈迪夫人的书》（Godey's Lady's Book）的编辑，这是一本19世纪美国流行的女性杂志。

海尔的感恩节运动

海尔多年来一直致力于使感恩节成为全国性的节日，他于1863年9月28日写信给林肯，敦促他发布一份公告。黑尔在信中提到，有这样一个全国性的感恩节将建立一个“美国大联盟节”

美国正处于内战的最深渊，也许林肯被一个节日的想法所吸引，这个想法将全国团结起来。当时林肯也在考虑发表一篇关于战争目的的演讲，这将成为葛底斯堡演讲。

林肯写了一份公告，于1863年10月3日发布。两天后，《纽约时报》发表了一份公告。

这个想法似乎很流行，北方各州在林肯公告中注明的日期庆祝感恩节，即1863年11月26日11月的最后一个星期四。

林肯的感恩节宣言

林肯1863年的感恩节宣言全文如下：

October 3, 1863 By the President of the United States A Proclamation The year that is drawing toward its close has been filled with the blessings of fruitful fields and healthful skies. To these bounties, which are so constantly enjoyed that we are prone to forget the source from which they come, others have been added, which are of so extraordinary a nature that they cannot fail to penetrate and soften the heart which is habitually insensible to the ever-watchful providence of Almighty God. In the midst of a civil war of unequaled magnitude and severity, which has sometimes seemed to foreign states to invite and provoke their aggressions, peace has been preserved with all nations, order has been maintained, the laws have been respected and obeyed, and harmony has prevailed everywhere, except in the theater of military conflict; while that theater has been greatly contracted by the advancing armies and navies of the Union. Needful diversions of wealth and of strength from the fields of peaceful industry to the national defense have not arrested the plow, the shuttle, or the ship; the ax has enlarged the borders of our settlements, and the mines, as well of iron and coal as of the precious metals, have yielded even more abundantly than heretofore. Population has steadily increased, notwithstanding the waste that has been made in the camp, the siege, and the battlefield, and the country, rejoicing in the consciousness of augmented strength and vigor, is permitted to expect continuance of years with large increase of freedom. No human counsel hath devised, nor hath any mortal hand worked out these great things. They are the gracious gifts of the Most High God, who while dealing with us in anger for our sins, hath nevertheless remembered mercy. It has seemed to me fit and proper that they should be solemnly, reverently, and gratefully acknowledged as with one heart and one voice by the whole American people. I do, therefore, invite my fellow-citizens in every part of the United States, and also those who are at sea and those who are sojourning in foreign lands, 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. And I recommend to them that, while offering up the ascriptions justly due to Him for such singular deliverances and blessings, they do also, with humble penitence for our national perverseness and disobedience, commend to His tender care all those who have become widows, orphans, mourners, or sufferers in the lamentable civil strife in which we are unavoidably engaged, and fervently implore the interposition of the Almighty hand to heal the wounds of the nation, and to restore it, as soon as may be consistent with the Divine purposes, to the full enjoyment of peace, harmony, tranquility, and union. In testimony whereof, I have hereunto set my hand and caused the seal of the United Stated States to be affixed. Done at the city of Washington, this third day of October, in the year of our Lord one thousand eight hundred and sixty-three, and of the Independence of the United States the eighty-eighth. -Abraham Lincoln