The history of Maryland’s state flag has its roots in the heraldic emblems of Maryland’s colonial founding family. The yellow and black quadrants of the flag reflect the colors of George Calvert’s paternal branch coat of arms, while the red and white quadrants stand for the colors in Calvert’s maternal branch coat of arms, the Crosslands. The use of both emblems in alternating flag quadrants reflects how the state overcame internal conflicts regarding allegiance to the union during the Civil War. A need for reconciliation and unity during the post-Civil War period led to the usage of both patterns within the same flag and the unofficial adoption of the alternating quadrant pattern that is used today in Maryland’s state flag. Although the colors were unofficially associated with the state of Maryland throughout the late 19th century, Maryland’s state flag was not officially adopted by the state until 9 March 1904.
All historical mentions of Maryland’s state flag prior to the revolution describe only Calvert’s yellow and black paternal heraldic emblem. After the end of the Revolutionary War, various other patterns eclipsed the popularity of the yellow and black flag, and Calvert’s emblem was all but forgotten. It was revived again in 1854, as the state of Maryland officially adopted a seal that featured the Calvert heraldic emblem on a blue background.
Shortly thereafter, the beginning of the Civil War prompted many of Maryland’s citizens to sympathize with secessionists. Although the state of Maryland officially sided with the Union, many of Maryland’s citizens were reluctant to use the colors of a Union state to represent them. These sympathizers adopted the red and white Crosslands family heraldic emblem as a symbol of their opposing views. Red and white clothing became a popular style among this group, causing the colors to become known as secessionist colors.
After the war, Maryland’s citizens became aware of a need to unify and reconcile. They sought a common identity as a state once again. At public events, banners that featured four alternating quadrants of Calvert and Crosslands colors were a frequent symbol of the new unified mindset. Although the original designer of the new design remains unknown, it began to be seen as an unofficial symbol of the state of Maryland by 1880.
In October 1889, Maryland’s largest segment of its military, the Fifth Regiment of the Maryland National Guard, officially adopted the four-color, four-quadrant design. This helped publicize and popularize the design and crystallize it as a symbol of Maryland’s history in the minds of Maryland’s citizens. On 9 March 1904, the current design was officially adopted by state government for use as Maryland’s state flag.