The U.S. president who experienced the most dramatic shift in public opinion decades after leaving office is Abraham Lincoln.
Initially, during his presidency and especially towards the end of the Civil War, Lincoln was not universally beloved. His decisions, particularly regarding the Emancipation Proclamation and his prosecution of the war, made him a polarizing figure. While he had strong support among abolitionists and Unionists, he faced significant opposition from those in the Confederacy and even some in the Northern states. His assassination in 1865 further complicated public opinion, as he became a martyr for the Union cause, but he was still a divisive figure for some at the time.
However, over the decades following his death, Lincoln's legacy underwent a profound transformation. By the late 19th and 20th centuries, historians and the public began to view him more favorably, recognizing his leadership during the nation's most perilous time, his commitment to ending slavery, and his preservation of the Union. Today, Lincoln is consistently ranked among the greatest U.S. presidents in historical polls, with a widely admired legacy for his vision, moral leadership, and dedication to democracy.
The shift from a figure with mixed popularity during his presidency to a nearly universally revered icon of American history is one of the most dramatic in U.S. presidential history.