They represent the counties of Charles, Calvert, and St. Mary's, which are located on the Southern Maryland peninsula between Chesapeake Bay and the Potomac River.

[6] Charles County initiated efforts to bring affiliated professional baseball, in the form of a relocated Class A Kinston Indians team, to the Southern Maryland region in 1985, but those plans fell through.

The progress made on the ballpark was reversed after Charles County commissioners voted against its financial support, instead deciding to funnel money to infrastructure projects.

[7] After Hughesville residents denied the ballpark, all focus was shifted to Waldorf, a bedroom community of Washington, D.C.[8] The Atlantic League formally announced an expansion team for Southern Maryland on February 15, 2006.

Initially, there was some concern about how the Blue Crabs would impact the attendance of the nearby Double-A Bowie Baysox, a Baltimore Orioles affiliate that plays approximately 32 miles (51 km) away.

In November 2016, the team was sold to a new ownership group, Crabs On Deck, LLC, headed by Frank Boulton, the founder and CEO of the Atlantic League and owner of the Long Island Ducks and Bridgeport Bluefish.

The Blue Crabs hold a series of charity events that benefit such organizations as the Southern Maryland Food Bank, The Salvation Army, Juvenile Diabetes Research Fund, Soldier's Angels, Orioles Advocates, and the American Red Cross.

Other events such as the Red Cross blood drive and Prostate Cancer Awareness Night are held at Regency Furniture Stadium to promote health and wellness.

[15] Prior to the 2009 season, the team partnered with the Charles County Hospice House to allow the non-profit charity to take advantage of theme nights for fundraising opportunities.

The mascot debuted on April 19, 2008, at the Charles County Youth League's opening day parade held at Laurel Springs Park in La Plata.