1. In 1791, the federal district's government passed the "Residence Act," which established a permanent national capital on the banks of the Potomac River, between Maryland and Virginia. This led to the creation of Washington D.C., as we know it today.

2. In 1850, Congress passed the "Compromise of 1850," which included the "Fugitive Slave Act," requiring the return of runaway slaves to their owners. This controversial law was enforced in the District of Columbia, leading to widespread protests and civil disobedience among abolitionists.

3. In 1862, during the American Civil War, Confederate forces under General Jubal A. Early began their invasion of Maryland and Pennsylvania. The raid culminated in the Battle of Fort Stevens, which took place in the District of Columbia on July 11-12, 1864.

4. In 1941, President Franklin D. Roosevelt signed the "Lend-Lease" bill into law, which authorized the U.S. to provide military aid to allied nations during World War II. The District of Columbia played an important role in the war effort, including the construction of the Pentagon and other military installations.

5. In 1954, the Supreme Court handed down its landmark decision in Brown v. Board of Education, which declared racial segregation in public schools unconstitutional. The District of Columbia, which was not a state and did not have its own school system, was required to comply with the ruling and integrate its schools.