April 8, 1913 – The 17th Amendment to the U. S. Constitution was ratified requiring direct popular election of U.S. Senators instead of being chosen by state legislators.
April 9, 1865 – General Robert E. Lee surrendered to General Ulysses S. Grant at Appomattox, effectively ending the Civil War.
April 11, 1968 – President Lyndon Johnson signs into law the Civil Rights Act of 1968. Generally called the Fair Housing Act, it expands on previous acts by adding federal enforcement provisions to prohibit discrimination in housing based on race, religion, and national origin. It was passed following the April 4th assassination of Rev. Dr. Martin Luther King, Jr., and subsequent civil unrest.
April 12, 1961 – Soviet Cosmonaut Yuri Gagarin becomes the first human in outer space. His 108-minute orbit of the earth propels him into international fame.