Battle of Antietam

More men were killed or wounded at Antietam on September 17, 1862, than on any other single day of the Civil War. Federal losses were 12,410, Confederate losses 10,700. Although neither side gained a decisive victory, Lee's failure to carry the war effort effectively into the North caused Great Britain to postpone recognition of the Confederate government. The battle also gave President Abraham Lincoln the opportunity to issue the Emancipation Proclamation, which, on January 1, 1863, declared free all slaves in States still in rebellion against the United States. Now the war had a dual purpose: to preserve the Union and end slavery.