Sykesville is a town in Carroll County, Maryland, United States. The population was 4,197 at the 2000 census.
The land on which Sykesville sits started out as part of a 3,000-acre (12 km2) Springfield Estate, owned by wealthy Baltimore shipbuilder William Patterson. In 1803, Patterson's daughter Elizabeth Patterson married Napoléon Bonaparte's brother Jérôme, but when she arrived in Europe as Jérôme's bride, Napoléon refused to let Betsy Patterson Bonaparte set foot on land. Napoleon refused the marriage of the two, and would not let Elizabeth set foot on France's soil. He was determined that Jerome marry into royalty, and sent Betsy back home. Denied by Napoleon, she was never able to see her husband again, leaving her to raise their son alone in the states. Upon the death of William in 1824, his son George Patterson inherited the estate.
In 1825, George Patterson sold 1,000 acres (4.0 km2; 1.6 sq mi) of Springfield Estate to his friend and business associate, James Sykes.