James M. Dennis was born in Dublin, Indiana in 1840. At 18 years of age he left home to begin his art education in Cincinnati, Ohio. While there he befriended Alexander Wyant, a famous landscape artist, and also studied with the portrait painter Joseph O. Eaton. In 1865 he successfully established a studio in Indianapolis, Indiana doing portrait and landscape work. The artist left Indianapolis for a brief period in 1873 for New York City to spend time with Eaton and Wyant. Returning home the next year, the artist spent a number of years pursuing his career before moving on to Detroit, Michigan, in 1883.

By 1900 the artist had begun to use pastels almost exclusively in his landscape and portrait work. He had initially used it for sketching but eventually became proficient enough to consider it his specialty. His portrait of Governor James A. Mount of Indiana was done in this medium. Dennis was a member of the Scarab Club and the Society of Western Artists. His work was exhibited for a number of years at the Michigan State Fair and also at the Detroit Institute of Art. The artist was also noted for his murals at the Hotel Cadillac in Detroit.