Despite an advanced career in metallurgy and a dedicated military appointment, Norman Kohlhepp developed an alternative career as a passionate artist alongside his wife, fellow artist, Dorothy Irene Smith Kohlhepp; they traveled extensively and often exhibited together.  

Kohlhepp was born in Louisville, Kentucky, and as a teenager he attended Manual Training High School graduating in 1910. He pursued further education at the University of Cincinnati in Ohio and earned a five-year degree in metallurgical engineering. His thesis was entitled: “The Effect of Surface Conditions Upon Corrosion.” For a short period of time he worked in Boston as a salesman for General Fireproofing Company, which sold metal office furniture. During World War I, in 1917, he went to France and enlisted with the French army as a member of the Réserve Mallet which served as a truck train that transported ammunition, tanks, and cannons to the frontlines. Up to this time the drivers had been French, but gradually more Americans became involved. He also trained mechanics and was promoted to first lieutenant, remaining abroad until 1919. He documented his time abroad in photographs of fellow soldiers and barracks, as well as the ruins of buildings. 

Through 1923, after his discharge, Kohlhepp resumed work with his former employer who had moved to Youngstown, Ohio. During 1924 he worked as an engineer for Hererle and Hay in Philadelphia, followed by a similar position, 1925 to 1932, for the Charles E. Bedaux Company of Illinois, a scientific management consulting firm with offices around the world. 

A skilled draughtsman of mechanical systems, Kohlhepp decided to pursue fine art studies in Paris, where he met his first wife, Dorothy, and founded the American Students and Artists Club. He studied at the Académie Colarossi and Académie de la Grande Chaumière. Kohlhepp and his wife also studied with André Lhote, the Cubist painter who exerted considerable influence on their painting styles; they continued to work under Lhote for many years. Lhote also taught other artists including Blanche Lazzell, Margaret Moffett Law, Josephine Sibley Couper, and Edith London.

Together the couple returned to his birthplace, Louisville. During the late 1930s, he was affiliated with the Courier-Journal, and then during the early 1940s with Reynolds Metal Company in the same city. Meanwhile he painted and exhibited alongside his wife. Among his favorite subjects were horses—a subject dear to many Kentuckians, along with numerous views of the Ohio River. His paintings are often infused with bright color and his landscapes in particular reveal Lhote’s influence and are often reminiscent of paintings by such German expressionists as Franz Marc. When a critic commented that his work was not cubistic, Kohlhepp responded: “Cubism was never an exact science.”