A leading iron producer during the Colonial period, Principio held Maryland’s first blast furnace, operating in 1725, and first refinery forge, constructed in 1728. After the American Revolution, Principio made cannons and other ordnance until the British destroyed the complex in a raid during the War of 1812. The Whitaker family revived the operation in 1837, and Principio remained an active iron manufacturing site for much of the nineteenth century.