On this day in 1863, President Abraham Lincoln delivered one of the most memorable speeches in American history. In just 272 words, Lincoln reminded a war-weary public why the Union had to fight, and win, the Civil War. The Battle of Gettysburg, fought four months earlier, was the single bloodiest battle of the war. Over the course of three days, more than 45,000 men were killed, injured, captured or went missing. It also proved to be a turning point as it marked the last Confederate invasion of Northern territory and the beginning of the Southern army's ultimate decline.