Abraham Lincoln (; February 12, 1809 – April 15, 1865) was an American statesman and lawyer who served as the 16th president of the United States (1861–1865). Lincoln led the nation through its greatest moral, constitutional, and political crisis in the American Civil War. He preserved the Union, abolished slavery, strengthened the federal government, and modernized the U.S. economy. Lincoln managed his own successful re-election campaign. He sought to reconcile the war-torn nation by exonerating the secessionists. On April 14, 1865, just days after the war's end at Appomattox, he was enjoying a night at the theatre with his wife Mary when he was assassinated by Confederate sympathizer and spy John Wilkes Booth. Lincoln died the next day. His marriage had produced four sons, two of whom preceded him in death, with severe emotional impact upon him and Mary. Lincoln is remembered as the United States' martyr hero, and he is consistently ranked as one of the greatest U.S. presidents.