The 16th President of the United States was Abraham Lincoln, who served from March 1861 until his assassination in April 1865. Lincoln is best known for leading the nation during the American Civil War and for his efforts to abolish slavery. He delivered the Emancipation Proclamation in 1863, declaring that all slaves in Confederate-held territory were to be set free. His leadership and commitment to preserving the Union and promoting equality have made him one of the most revered figures in American history. Lincoln's legacy continues to influence modern politics and civil rights.