1. On May 20, 1633, the first English colonists arrived in Maryland. Led by Leonard Calvert, the group established a settlement at St. Mary's City and began laying the groundwork for the colony's agricultural economy.

2. May 20, 1774, saw the convening of the Maryland Revolutionary Convention in Annapolis. The convention was attended by delegates from across the state and ultimately passed a resolution supporting the boycott of British goods in protest of the Intolerable Acts.

3. One of the most notable events in Maryland history took place on May 20, 1861, when the state was officially admitted to the Confederacy. Despite being a slave state, Maryland initially resisted secession, but ultimately joined the Confederacy following a period of tension and political maneuvering.

4. On May 20, 1932, the US Navy commissioned its largest aircraft carrier to date, the USS Lexington. The ship, which would go on to serve in World War II and earn the nickname "Lady Lex," was initially based in Annapolis before being relocated to different ports around the world.

5. In 2009, the state of Maryland took a historic step towards legalizing same-sex marriage on May 20 when the State Senate voted in favor of a bill recognizing such unions. Although the bill ultimately failed to pass the State House, it marked an important milestone in the fight for LGBTQ+ rights in Maryland and beyond.