when banks arrived at winchester, he started organizing his defenses. on may 25, jackson's first attack was thrown back. ewell approached winchester from the southwest with his division and attacked camp hill (now overlook park in the southeastern part of winchester). 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. this was the decisive victory for jackson's valley campaign.