High Quality Content by WIKIPEDIA articles! The 25th President of the United States, William McKinley, was shot and fatally wounded on September 6, 1901, inside the Temple of Music on the grounds of the Pan-American Exposition in Buffalo, New York. McKinley was shaking hands with the public when he was shot by Leon Czolgosz, an anarchist. The President died on September 14 from gangrene caused by the bullet wounds.