Abraham Lincoln is often referred to as "the Great Emancipator" due to his pivotal role in ending slavery in the United States. He issued the Emancipation Proclamation in 1863, which declared that all enslaved people in the Confederate states were to be set free. Lincoln's leadership during the Civil War and his commitment to the ideals of freedom and equality solidified his legacy as a champion of civil rights. His actions not only helped to shape the course of American history but also laid the groundwork for future civil rights movements.