Born in Baltimore, Maryland in 1812, the fourth child and second son of Amzi Bateman (c.1777–1816), a fisherman, and his wife, Catherine Bateman (née Schaeffer) (c.1784–1870). Amzi Bateman had served with the 6th Regiment of the Maryland Militia and took part in the defence of Baltimore against the invasion by the British troops during the Anglo-American War of 1812. After his death in 1816 his widow tutored students to support herself and her children.