1. In 1794, the first execution by hanging took place in the newly created District of Columbia. James Greenleaf, a land speculator, was convicted of forgery and sentenced to death.

2. On July 27, 1861, the Union Army scored a decisive victory over Confederate forces in the Battle of Bull Run. This was the first major battle of the American Civil War and marked the beginning of a long and bloody conflict.

3. In 1948, President Harry Truman signed Executive Order 9981, which desegregated the armed forces of the United States. This was a landmark moment in the civil rights movement and helped pave the way for further progress in the fight against segregation.

4. In 1960, the Washington Senators became the first team in Major League Baseball history to play a regular season game on artificial turf. The game was played at Houston's Colt Stadium, which had recently installed an AstroTurf playing surface.

5. On July 27, 1996, a bomb exploded at the Summer Olympics in Atlanta, killing two people and injuring more than 100 others. The attack was carried out by a domestic terrorist named Eric Rudolph, who was eventually captured and sentenced to life in prison.