Rep. John Thomson Mason, (D-MD)

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US Congressman. Ater graduating from Princeton College in 1836, he studied law, was admitted to the bar, and established a practice in Hagerstown, Maryland. Elected to Congress as a Democrat from Maryland in 1840, he served a single term, from 1841 to 1843. He was collector of customs in Baltimore from 1857 to 1861, before retiring to Annapolis, where he died.

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John Thomson Mason, Jr. was a grandnephew of George Mason (1725–1792); grandson of Thomson Mason (1733–1785);[1][2] nephew of Stevens Thomson Mason (1760–1803); son of John Thomson Mason (1765–1824) and Elizabeth Beltzhoover Mason (1781–1836);[1][2] second cousin of Thomson Francis Mason (1785–1838);[1][2] first cousin of Armistead Thomson Mason (1787–1819), John Thomson Mason (1787–1850), and James Murray Mason (1798–1871);[1][2] and first cousin once removed of Stevens Thomson Mason (1811–1843).[1][2]