1. The District of Columbia was founded on August 1, 1790
On August 1, 1790, the Residence Act was passed by the United States Congress, which brought the federal government to a new permanent capital, which was located on the Potomac River. The capital was named the District of Columbia (DC).

2. Abraham Lincoln signed the Emancipation Act on August 1, 1862
On August 1, 1862, President Abraham Lincoln signed the Emancipation Act, which declared that all slaves held in the Confederate states shall be forever free. This was a significant move towards ending slavery in the United States.

3. Women's suffrage parade held on August 1, 1914
On August 1, 1914, a major women's suffrage parade was held in Washington, DC, which is said to have been one of the largest suffrage parades in the nation's history. Thousands of women marched in support of the right to vote.

4. DC granted home rule on August 1, 1972
On August 1, 1972, the District of Columbia was granted home rule, which gave residents the power to elect their own mayor and city council. This was a major step towards self-governance for the District.

5. Metro system opened on August 1, 1976
On August 1, 1976, the Washington Metro, also known as the Metrorail, officially opened for service. This subway system serves the District of Columbia and its surrounding areas, and is an important mode of transportation for locals and tourists alike.