when banks arrived at winchester, he started organizing his defenses. jackson's army approached from the south while ewell's army approached from the southeast. on may 25, jackson's forces made their first attack, but were thrown back. ewell's division attacked camp hill. at the same time jackson's louisiana brigade outflanked, then overran the union position on bower's hill (southwestern part of winchester). with their flanks broken, the union troops began a disorganized retreat through the city of winchester. even citizens of winchester fired on the union soldiers. banks retreated across the potomac river back into maryland. as a result of the battle, banks lost about 2,000 men and nearly all of his supplies. the total confederate casualties numbered only about 400. this was the decisive victory for jackson's valley campaign.