President McKinley was assassinated on September 6, 1901. He was shot by anarchist Leon Czolgosz during a public event at the Pan-American Exposition in Buffalo, New York. McKinley initially survived the attack but succumbed to his wounds on September 14, 1901. His assassination had profound implications for the United States, leading to the presidency of Theodore Roosevelt. Roosevelt's administration marked a shift in domestic and foreign policy, emphasizing progressive reforms and a more assertive role for the U.S. on the global stage, particularly regarding imperialism.