[2] Born at the Montpelier estate near Hagerstown, Maryland, Mason was educated by a private tutor and graduated from Princeton College in 1836.

He studied law, was admitted to the bar, and commenced practice in Hagerstown in 1838.

Mason later served as a member of the Maryland House of Delegates in 1838 and 1839, and was elected as a Democrat to the Twenty-seventh Congress, serving one term from March 4, 1841, to March 3, 1843.

Mason died on March 28, 1873, in Elkton, Maryland at age 57.

Mason married Margaret Augusta Cowan in Alleghany City, Pennsylvania on December 14, 1842.