- 1806 – Construction is authorized for the Great National Pike, better known as the Cumberland Road, which became the first United States federal highway.
- 1848 – Niagara Falls stops flowing for 30 hours due to an ice jam
- 1865 – Appomattox, the final campaign in the Civil War, begins.
- 1885 – Frances Bolton is born. She created an endowment to build a school of nursing at Case Western Reserve in 1923 after working with the Visiting Nurse Association and seeing the homes of the desperately poor. She helped remove color lines in nursing, and as a Republican Congresswoman from Ohio, she worked for racial equality and equal pay. She also is the only woman to have served in Congress simultaneously with her son, who represented a district to the east of his mother’s.
- 1929 – President Herbert Hoover has a phone installed at his desk in the Oval Office of the White House, the first president to do so.
- 1951 – Julius and Ethel Rosenberg are convicted of espionage for their role in passing atomic secrets to the Soviets. They were executed on June 19, 1953 in Sing Sing Prison in New York. Both maintained their innocence to the end.
- 1973 – The last US soldiers leave Vietnam.
- 1974 – Chinese farmers discover the Terracotta Army near Xi’an, 8,000 clay warrior statues buried to guard the tomb of China’s 1st emperor, Qin Shi Huang.
- 1993 – Catherine Callbeck becomes the first woman in Canada to be elected as premier.
