James Hennessey has lived in Baltimore, Maryland since 1965. He grew up in Oak Park, the Chicago suburb that was home to Ernest Hemingway and Frank Lloyd Wright. Hennessey earned his undergraduate degree at Illinois Wesleyan University and a graduate degree at the University of Colorado, Boulder, where he studied with Richard Diebenkorn, Wendell Black, and Roland Reiss. While at Boulder, he was selected to represent Colorado at the Yale Summer School at Norfolk, Connecticut. At that time, Hennessey's work was influenced by the San Francisco Figurative painters.
In 1962, one of Hennessey's paintings was included in the Museum of Modern Art's exhibition, "Recent Painting U.S.A., The Figure." The show was a juried exhibit that toured the country after the New York opening. In the same year, the American Academy in Rome awarded Hennessey "The Rome Prize." He was in residence for two years in Rome and exhibited in several prominent galleries in the city and had a one-man exhibition in Milan. In 1965 Hennessey joined the faculty of the Maryland Institute, College of Art in Baltimore. While in Baltimore he accrued an extensive exhibition record, with works shown in New York at the Marilyn Pearl Gallery, in Boston at the Boris Mirski and the Alpha Galleries and in Washington, DC at the Pensler Galleries, among many others.
James Hennessey has also traveled extensively, and his studio work has been informed by these experiences. Hennessey has directed programs for students, faculty, and professional artists in Italy and in France, including the Maryland Institute, College of Art Italian Program in Sorrento, Italy, and the Alfred and Trafford Klots Residency Program, Rochefort-en-Terre, France.