Romanzo Norton Bunn was a United States federal judge.
Bunn, Romanzo was born on September 24, 1829 in S. Hartwick, Otsego Company, New York, United States.
Born in South Hartwick, New York, Bunn read law to enter the Bar in 1853. He was in private practice in Ellicottville, New York from 1853 to 1854, and then in Galesville, Wisconsin until 1861. He was district attorney of Galesville from 1857 to 1858.
He was a judge of Wisconsin Circuit Court, 6th Judicial Circuit from 1868 to 1877. He was a Professor of law, University of Wisconsin from 1878 to 1885. On October 25, 1877, Bunn was nominated by President Rutherford B. Hayes to a seat on the United States District Court for the Western District of Wisconsin vacated by James C. Hopkins.
Bunn was confirmed by the United States Senate on October 30, 1877, and received his commission the same day. Bunn served in that capacity until his retirement, on January 9, 1905. He died in Madison, Wisconsin.
He was a member of the Wisconsin State Assembly in 1859, returning to private practice in Sparta, Wisconsin from 1861 to 1868.