Fought in Gettysburg, Pennsylvania this was the second and last invasion of the south into northern territory. This battle had the most casualties in the entire war. Fought from July 1st to the 3rd, 1863, General Lee's army battled General Mead's army from the Potomac. The battle went back and forth, but eventually the north prevailed. Pickett's charge represented the water mark for the Confederacy's invasion. Lee then led a torturous retreat back to Virginia. It is estimated that there were between 46,000 and 51,000 casualties during the 3 day battle. President Lincoln gave a speech four and a half months later, commemorating the Gettysburg National Cemetery. This speech is known as the Gettysburg address and is one of the most famous speeches in American history. In it, Lincoln reflects on why the nation must prevail in the war, and how the men that died will not have died in vain.