Here are 5 historical events that took place on May 18 in the District of Columbia:

1. In 1860, the Republican National Convention was held at the Capitol building in Washington, D.C. It was the first political convention ever held in the city.

2. In 1896, the Supreme Court of the United States ruled in Plessy v. Ferguson that "separate but equal" segregation of railroad cars was constitutional, paving the way for Jim Crow laws and other forms of discrimination across the country.

3. In 1954, the Supreme Court of the United States issued its landmark decision in Brown v. Board of Education, ruling that segregation in public schools was unconstitutional and sparking a nationwide civil rights movement.

4. In 1973, the Senate Select Committee on Watergate began public hearings into the Watergate scandal, which would lead to the resignation of President Richard Nixon and the indictment of several high-ranking officials.

5. In 2004, the World War II Memorial was dedicated on the National Mall in Washington, D.C. The monument honors the approximately 16 million Americans who served in the armed forces during the war, including the more than 400,000 who died.