John McLean was born March 11, 1785, in Morris County, New Jersey, finally settling with his parents in Lebanon, Ohio, where he studied law with private tutors. McLean was admitted to the Ohio bar in 1807 and was later elected to the U.S. House of Representatives as a Republican (1813-1816). He went on to become an associate judge on the Ohio Supreme Court (1816-1822) and commissioner of General Land Office (1822). McLean was appointed postmaster general by President James Monroe and was reappointed to that position by President John Quincy Adams (1825-1829). He declined offers of cabinet positions in administration of President Andrew Jackson, opting for the post of associate justice of the U.S. Supreme Court (1829), where he served until his death on April 4, 1861.