When John B. Minor reached the age of seventy in 1890, the Board of Visitors allowed him to hire a assistant to aid in his teaching. His son, John B. Minor, Jr., served in this position for two years, followed by Minor’s second son, Raleigh Colston Minor (perhaps the namesake of Minor's good friend, Raleigh E. Colston), who became an assistant in the School of Common and Statute Law in 1893. Minor received three degrees from UVA—the B.A. in 1887, M.S. in 1888, and LL.B. in 1890. He practiced law in Richmond for three years before joining the UVA faculty. From 1895-99 he served as an adjunct professor before becoming full professor, his position from 1899-1923. Minor taught criminal law, criminal procedure, and real property. He served as acting dean from 1907-08. He died in 1923.

Minor authored numerous law review articles and seven books, the first of which he published at the young age of twenty-five. Four years later, he followed this first book, An Analytical Abstract of Greenleaf on Evidence, with a second one, Law of Tax Titles in Virginia. He gained greater notice from his 1901 book Conflict of Laws; or Private International Law, published by Little, Brown of Boston. In 1908 Minor established his reputation as an expert  on real property with his publication of the Law of Real Property, a two-volume treatise. Raleigh Minor expanded his interest in the field of international law during World War I, delivering papers before the American Society of International Law during that time. This led to his 1918 publication of A Republic of Nations, which advocated a union of nations in order to avoid further wars.