Once the American Civil War began in 1861, Philadelphia's southern leanings were reduced. Popular hostility shifted against southern sympathizers. Mobs threatened a secessionist newspaper and the homes of suspected sympathizers, and were only turned away by the police and Mayor Alexander Henry. Philadelphia supported the war with soldiers, ammunition, and war ships and its manufacturers produced many army uniforms. Philadelphia was also a major receiving place of the wounded, with more than 157,000 soldiers and sailors treated within the city. Philadelphia began preparing for invasion in 1863, but the Confederate Army was repelled by Union forces at Gettysburg.