William McKinley died on September 14, 1901.
Assassination of William McKinley . McKinley initially appeared to be recovering , but took a turn for the worse on September 13 as his wounds became gangrenous , and died early the next morning ; Vice President Theodore Roosevelt succeeded him . William McKinley . However , his legacy was quickly cut short when he was shot on September 6 , 1901 by Leon Czolgosz , a second-generation Polish-American with anarchist leanings ; McKinley died eight days later , and was succeeded by his Vice President Theodore Roosevelt .