Janson taught at the
St. Louis School of Fine Arts at
Washington University from 1941 until 1948, where he also took charge of a renewal of the University Art Gallery collection (now known as the
Mildred Lane Kemper Art Museum). Janson's plan to sell popular canvases such as
Frederic Remington's
A Dash for the Timber at the New York galleries of the
Kende family drew comment from the local paper, wondering why St. Louisans had not been given preference. Janson sold 120 artworks, retained 80, and acquired 40 works by European modernists through the Kende Galleries:
Paul Klee,
Juan Gris,
Theo van Doesburg. Janson left in 1948 to join the faculty of
New York University, where he developed the undergraduate arts department and taught at the graduate
Institute of Fine Arts. Also in 1948 he was awarded a
Guggenheim Fellowship. He was recognized with an honorary degree in 1981, and died on a train between
Zurich and
Milan in 1982 at the age of 68. He wrote about
Renaissance art and nineteenth-century
sculpture, and authored two prize-winning books,
Apes and Ape Lore in the Middle Ages and the Renaissance (1952) and
Sculpture of Donatello (1957). In his later years he was concerned with East–West dialogue in the arts. Over his career, Janson consulted on the
Time–Life Library of Art; was president of the
College Art Association, editor of the
Art Bulletin, and founding member and President of the
Renaissance Society of America. He also wrote books on art for young people, some in collaboration with his wife. Janson's signature contribution to the discipline of art history, specifically to the teaching of art history, is his survey text entitled simply
History of Art, which was first published in 1962 and has since become the standard by which current art history textbooks are measured. ==Feminist critiques==