1. On March 13, 1868, the Maryland state legislature ratified the 14th Amendment to the United States Constitution which granted citizenship and equal protection under the law to African Americans.

2. On March 13, 1954, the U.S. Supreme Court heard arguments in Brown v. Board of Education, a landmark case that challenged racial segregation in public schools. The case originated in Topeka, Kansas, but was one of five cases that were consolidated under Brown. The Supreme Court ultimately ruled that segregation in public schools was unconstitutional.

3. On March 13, 1984, the Baltimore Colts football team moved to Indianapolis. The move was controversial and unpopular among fans in Baltimore, and it would be 12 years before the city was awarded a new NFL franchise, the Baltimore Ravens.

4. On March 13, 2008, Maryland became the first state in the country to approve a statewide ban on arsenic in chicken feed. Arsenic had been used as a feed additive for many years to promote growth and keep chickens healthy, but concerns about the potential health effects of consuming arsenic-contaminated chicken led to the ban.

5. On March 13, 2019, Maryland lawmakers approved a bill that would allow terminally ill patients to legally end their lives with medication prescribed by a physician. The bill was signed into law on April 5th of that year, making Maryland the seventh state in the U.S. to legalize assisted suicide.