1901 — Willis Carrier invents a forerunner of the air conditioner and King C. Gillette begins manufacturing the modern safety razor with disposable blades. Elsewhere that year:

• President McKinley is assassinated by an anarchist at the Pan-American Exposition in Buffalo, N.Y. Theodore Roosevelt becomes President.
• U.S. citizenship is granted to the Five Civilized Tribes: the Cherokees, Creeks, Choctaws, Chickasaws and Seminoles.
• Wilhelm Maybach, the technical director at the Daimler works, builds the first Mercedes car.