Justice Barbour was born in Orange County, Virginia, in the upper central part of the state where he grew up, spent his entire professional life and from which he would be appointed to the Supreme Court of the United States. He did not complete any formal university education, which was not uncommon for the era.
In 1800, Justice Barbour entered private practice in Kentucky before moving back to Orange County in 1802, where he practiced law for the next decade. Justice Barbour was then a Virginia State Delegate from 1812 to 1815, when he was elected to be a Member of the United States House of Representatives, where he world serve continuously until 1830 (except for a brief departure from that body from 1825 to 1827). He worked his way up the ranks while in national politics, even serving as the 12th Speaker of the U.S. House from 1821 until Henry Clay’s defeat of his attempt to hold onto the office in 1823. He served as a Judge of the General Court of Virginia during his absence from the U.S. House (specifically from 1825 to 1827), and was appointed by President Andrew Jackson to be a Judge of the United States District Court for the Eastern District of Virginia in 1830 (the United States Senate would ultimately confirm him), where he would remain until his elevation to the SCUS.
Justice Barbour was nominated by President Jackson on December 28, 1835, to a seat vacated by Justice Gabriel Duvall. He was confirmed by the U.S. Senate on March 15, 1836, and received his commission that day. Justice Barbour took the Judicial Oath to officially join the SCUS on May 12, and served very briefly on the Marshall Court before spending the bulk of his SCUS career on the Taney Court. His service was terminated on February 25, 1841, due to his death.
Justice Barbour did not have a particularly distinguished career on the SCUS, and did not even stay on the Court long enough to take part in the most pivotal decision of his era, Dred Scott v. Sanford (1857). In terms of ideology, Justice Barbour was very much a part of Virginia's slaveholding plantation elite, and his values promoted the interests of his class; this meant that he supported states' rights, and opposed both federally-sponsored internal improvements and the second Bank of the United States. Regrettably, he was also a vigorous defender of slavery. The only particularly consequential decision Justice Barbour authored was in New York v. Miln (1837), which featured one of the earliest instances wherein the SCUS invoked a state’s "police power" – the supposed right of a sovereign to take all necessary steps to protect the health, safety, and welfare of its citizens – to justify upholding a law as constitutional.