Leonardtown Town Hall is located at 41660 Courthouse Drive, Leonardtown, MD 20650.
In 1708 the Maryland State Legislature received a petition from St. Mary's County to establish a county seat and construct a courthouse on Britton's bay on land commonly called "Sheppards Old Fields." It was later renamed "Seymour Towne" in 1710 and "Leonardtown" after Leonard Calvert. While established in the early 18th century, however, Leonardtown features historic resources that date from the mid-19th to the mid-20th centuries.
It was not until the late-19th and early-20th century that Leonardtown fully developed as a commercial and financial hub of St. Mary's County. Situated on or near the public square, the ca. 1921 First National Bank of St. Mary's, ca. 1914 Leonardtown Bank of the Eastern Shore Trust Company, 1939 Duke's Fountain-Bar-Restaurant, and 1939 Bell Motor Company Building all represented prominent buildings that testified to Leonardtown's maturation. In the mid-20th century population growth associated with the growth of the Patuxent Naval Air Station caused the construction of several low and medium income subdivisions for returning veterans including Longmore's Subdivision. With this increased population, the town increasingly became the site of recreation and entertainment facilities such as the St. Mary's Theater and the New Theater. Overall, Leonardtown retains a significant degree of historical integrity. The town's built landscape recalls the community's historic role as the governmental, religious, recreational, financial and commercial center of St. Mary's County.