The land on which Clifton Park sits was once farmland. Built around 1803, the home was originally the summer residence of Capt. Henry Thompson, (1774-1837). Born in Sheffield, England, he came to Baltimore around 1794, and soon became a prominent figure in the newly emerging city as a merchant, financier, and company director. Thompson was public-spirited and used his knowledge of horses in military matters to serve as a cavalry officer in the Maryland State Militia's "Baltimore Light Dragoons", which he joined in 1809 and was elected captain. He later organized the "First Baltimore Horse Artillery" in 1813, which defended Baltimore during the British attack during the War of 1812 at the Battle of Baltimore, the bombardment of Fort McHenry which inspired the writing of the "Star Spangled Banner". the Battle of North Point, and the stand-off at what is now known as Patterson Park in East Baltimore, on September 12-13-14, 1814. Prior to seeing action in Baltimore, he was assigned by Brig. Gen. John Stricker, commander of the Third Brigade (also known as the Baltimore City Brigade) of the Maryland State Militia, to carry messages between Bladensburg, Maryland, and the nearby national capital in Washington, D.C., during the first phase of the Battle of Bladensburg, which preceded the Burning of Washington during the Chesapeake Bay campaign in August 1814. Later he and his mounted unit served as the personal bodyguard of Maj. Gen. Samuel Smith, overall commander of the State Militia under then-Maryland governor Levin Winder, and the various militia forces from surrounding counties and states, including several regular army and navy units and detachments defending Baltimore in September 1814.