1. The first American soldier killed in action during World War I was Private Thomas Enright from Maryland. On May 31, 1918, Enright was part of a patrol near the Marne River in France when he was shot by a German sniper. He was posthumously awarded the Distinguished Service Cross for his bravery.

2. On May 31, 1921, the Baltimore Symphony Orchestra gave its first performance at the Lyric Theatre. The ensemble was founded by a group of local musicians and has since become one of the country's leading regional orchestras.

3. Frances Ellen Watkins Harper, an African American poet, lecturer, and abolitionist who was born in Baltimore, died on May 31, 1911. Harper was a prolific writer and speaker who advocated for social justice and women's rights.

4. On May 31, 1955, the Maryland Court of Appeals ruled that racial segregation on public golf courses was unconstitutional. The case was brought by a group of African American golfers who were denied entry to a municipal golf course in Baltimore.

5. The Chesapeake and Ohio Canal, which runs 184.5 miles from Cumberland, Maryland to Georgetown in Washington, D.C., was officially opened on May 31, 1828. The canal was built to transport coal from the Allegheny Mountains to the eastern seaboard and played a key role in the growth of industry and commerce in the Mid-Atlantic region.