Officially adopted by law on March 9, 1904, the Maryland State Flag is the only state flag based on heraldic emblems. The design of the flag is taken from the shield in the coat of arms of the Calvert family, the colonial proprietors of the state of Maryland. The coat of arms adopted by George Calvert, the first Lord Baltimore, included a shield that combined the yellow and black colors of his paternal family and the red and white colors of his maternal family, the Crosslands. (NOTE: There is contention that the red and white colors identified as those of the Crosslands is a misrepresentation. It is said that the colors are those of the Mynne family, the family name of Anne Calvert, wife of George Calvert). The arms of the Calvert and Crossland (Mynne) families are displayed in diagonally opposing quadrants of the flag.

Outdoor flags available in nylon (digital dyed) or 2-ply polyester material (screen dyed) to meet the most demanding commercial and residential uses. All outdoor flags are finished with polyester heading and brass grommets. Indoor flags in nylon (digital dyed) with pole hems and available plain or fringed. Stick flags available in lightweight polyester or silk-like material.