1. President Abraham Lincoln was assassinated by John Wilkes Booth on April 14, 1865, shortly after the end of the Civil War.
2. Congress disagreed with President Andrew Johnson's lenient Reconstruction plan, which readmitted southern states quickly. This led to Johnson's impeachment in 1868 for firing the Secretary of War without Congressional approval.
3. In 1870, Hiram Revels of Mississippi became the first African American to serve in the U.S. Senate, while Blanche K. Bruce of Mississippi was the first African American to serve a full term, reflecting some progress during Reconstruction but also persistent racism.