President: Dwight D. Eisenhower (Republican)
Vice President: Richard Nixon (Republican)

Chief Justice: Earl Warren
Speaker of the House of Representatives: Joseph William Martin, Jr. (R-Massachusetts) (until January 3), Sam Rayburn (D-Texas) (starting January 3)
Senate Majority Leader: William F. Knowland (R-California) (until January 3), Lyndon B. Johnson (D-Texas) (starting January 3)

Congress: 83rd (until January 3), 84th (starting January 3)

January 22 – The Pentagon announces a plan to develop ICBMs (intercontinental ballistic missiles) armed with nuclear weapons.
February 12 – U.S. President Dwight D. Eisenhower sends the first U.S. advisors to South Vietnam.
April 12 – The Salk polio vaccine, having passed large-scale trials earlier in the United States, receives full approval by the FDA.
April 15 - Ray Kroc opens his first McDonald's in Des Plaines, Illinois.
September 10 – Gunsmoke debuts on the CBS television network.
December 1 – Rosa Parks is arrested for refusing to give up her seat on a bus to a white person, and the national civil rights movement begins.
December 31 – General Motors becomes the first American corporation to make over USD 1 billion in a year.