The last Thursday in November is declared as Thanksgiving Day by United States President Abraham Lincoln as are Thursdays, November 30, 1865 and November 29, 1866.

Abraham Lincoln ( LINK-n; February 12, 1809 April 15, 1865) was an American lawyer and statesman who served as the 16th president of the United States from 1861 until his assassination in 1865. Lincoln led the nation through the American Civil War and succeeded in preserving the Union, abolishing slavery, bolstering the federal government, and modernizing the U.S. economy.

Lincoln was born into poverty in a log cabin in Kentucky and was raised on the frontier, primarily in Indiana. He was self-educated and became a lawyer, Whig Party leader, Illinois state legislator, and U.S. Congressman from Illinois. In 1849, he returned to his law practice but became vexed by the opening of additional lands to slavery as a result of the KansasNebraska Act of 1854. He reentered politics in 1854, becoming a leader in the new Republican Party, and he reached a national audience in the 1858 Senate campaign debates against Stephen Douglas. Lincoln ran for President in 1860, sweeping the North to gain victory. Pro-slavery elements in the South viewed his election as a threat to slavery, and Southern states began seceding from the Union. During this time the newly formed Confederate States of America began seizing federal military bases in the south. Just over one month after Lincoln assumed the presidency, the Confederate States attacked Fort Sumter, a U.S. fort in South Carolina. Following the bombardment, Lincoln mobilized forces to suppress the rebellion and restore the Union.

Lincoln, a moderate Republican, had to navigate a contentious array of factions with friends and opponents from both the Democratic and Republican parties. His allies, the War Democrats and the Radical Republicans, demanded harsh treatment of the Southern Confederates. Anti-war Democrats (called "Copperheads") despised Lincoln, and irreconcilable pro-Confederate elements plotted his assassination. He managed the factions by exploiting their mutual enmity, carefully distributing political patronage, and by appealing to the American people. His Gettysburg Address came to be seen as one of the greatest and most influential statements of American national purpose. Lincoln closely supervised the strategy and tactics in the war effort, including the selection of generals, and implemented a naval blockade of the South's trade. He suspended habeas corpus in Maryland, and he averted British intervention by defusing the Trent Affair. In 1863 he issued the Emancipation Proclamation, which declared the slaves in the states "in rebellion" to be free. It also directed the Army and Navy to "recognize and maintain the freedom of such persons" and to receive them "into the armed service of the United States." Lincoln also pressured border states to outlaw slavery, and he promoted the Thirteenth Amendment to the United States Constitution, which upon its ratification abolished slavery.

Lincoln managed his own successful re-election campaign. He sought to heal the war-torn nation through reconciliation. On April 14, 1865, just days after the war's end at Appomattox, he was attending a play at Ford's Theatre in Washington, D.C., with his wife Mary when he was fatally shot by Confederate sympathizer John Wilkes Booth. Abraham Lincoln is remembered as a martyr and a national hero for his wartime leadership and for his efforts to preserve the Union and abolish slavery. Lincoln is often ranked in both popular and scholarly polls as the greatest president in American history.

Thanksgiving is a federal holiday in the United States, celebrated on the fourth Thursday of November. It is sometimes called American Thanksgiving (outside the United States) to distinguish it from the Canadian holiday of the same name and related celebrations in other regions. It originated as a day of thanksgiving and harvest festival, with the theme of the holiday revolving around giving thanks and the centerpiece of Thanksgiving celebrations remaining a Thanksgiving dinner. The dinner traditionally consists of foods and dishes indigenous to the Americas, namely turkey, potatoes (usually mashed or sweet), stuffing, squash, corn (maize), green beans, cranberries (typically in sauce form), and pumpkin pie. Other Thanksgiving customs include charitable organizations offering Thanksgiving dinner for the poor, attending religious services, watching parades, and viewing football games. In American culture Thanksgiving is regarded as the beginning of the fall–winter holiday season, which includes Christmas and the New Year.

New England and Virginia colonists originally celebrated days of fasting, as well as days of thanksgiving, thanking God for blessings such as harvests, ship landings, military victories, or the end of a drought. These were observed through church services, accompanied with feasts and other communal gatherings. The event that Americans commonly call the "First Thanksgiving" was celebrated by the Pilgrims after their first harvest in the New World in October 1621. This feast lasted three days and was attended by 90 Wampanoag Native American people and 53 Pilgrims (survivors of the Mayflower). Less widely known is an earlier Thanksgiving celebration in Virginia in 1619 by English settlers who had just landed at Berkeley Hundred aboard the ship Margaret.Thanksgiving has been celebrated nationally on and off since 1789, with a proclamation by President George Washington after a request by Congress. President Thomas Jefferson chose not to observe the holiday, and its celebration was intermittent until President Abraham Lincoln, in 1863, proclaimed a national day of "Thanksgiving and Praise to our beneficent Father who dwelleth in the Heavens", calling on the American people to also, "with humble penitence for our national perverseness and disobedience .. fervently implore the interposition of the Almighty hand to heal the wounds of the nation...". Lincoln declared it for the last Thursday in November. On June 28, 1870, President Ulysses S. Grant signed into law the Holidays Act that made Thanksgiving a yearly appointed federal holiday in Washington D.C. On January 6, 1885, an act by Congress made Thanksgiving, and other federal holidays, a paid holiday for all federal workers throughout the United States. Under President Franklin D. Roosevelt, the date was moved to one week earlier, observed between 1939 and 1941 amid significant controversy. From 1942 onwards, Thanksgiving, by an act of Congress, signed into law by FDR, received a permanent observation date, the fourth Thursday in November, no longer at the discretion of the President.