Painter, architect, and railroad aficionado, Albert Sheldon Pennoyer was born in Oakland, California on April 5, 1888. His early education was spent at boarding schools in Lawrenceville, New Jersey, and Geneva, Switzerland, where he developed a consuming curiosity for the mechanics of how things work. He attended the University of California, Berkeley for one year before moving to Paris to study architecture at the École des Beaux Arts. Inspired by the City of lights, Pennoyer’s curiosity soon turned to paint. In addition to periods of study at the Académie de la Grand Chaumière, the Académie Julian, and the Pennsylvania Academy of Fine Arts in Philadelphia, Pennoyer traveled across Europe as a pupil of such prominent artists of the time as Giuseppe Casciaro and Harold Speed. 

Upon the outbreak of World War I, Pennoyer returned to the United States. Called to active duty in 1917, he served with the camouflage unit of the U.S. Army Corps of Engineers until 1920, when he joined the Officers’ Reserve Corps. In 1921 he opened his own studio on the Upper East Side of Manhattan, which he would maintain for nearly forty years. His paintings, executed in pastel, gouache, watercolor, and oils, were successfully exhibited at the Panama Pacific International Exposition, Golden Gate Park Museum, Los Angeles County Museum of Art, and several prominent galleries in New York and California.

Pennoyer was once again called to action during World War II. He served in the U.S. Army Air Force and the U.S. Army Corps of Engineers before being assigned as an MFAA Officer in North Africa and Italy. During his service as a Monuments Man, he was involved in the safeguarding, repair, and recovery of Italy’s rich cultural heritage, which faced destruction from bombing, looting, and exposure to the elements. Pennoyer worked alongside Monuments Men Capt. Basil Marriott and Lt. Col. John Bryan Ward-Perkins in Rome, Capt.Roderick Enthoven and Lt. Frederick Hartt in Florence, and Capt. Deane Keller in Pisa. He also participated in the recovery effort at numerous art repositories in the Tuscan countryside, where Florentino officials had evacuated hundreds of works of art from churches and public collections, principally the Uffizi Gallery, Pitti Palace, and Bargello. 

The surviving photographic record of the work of the Monuments Men in Italy is largely due to the tireless efforts of Pennoyer. Armed with a Leica camera, he photographed not only the physical devastation which war had unleashed upon Italy but the emotional toll it had exacted from its citizens. Photographs of his fellow Monuments Men record their dedication to preserving many of Italy’s most important cultural treasures. In the words of Monuments Man Lt. Col. Ernest T. DeWald," Pennoyer has spared himself no end to secure materials which were almost inaccessible to us and to build up this photographic record for Washington and London." The A. Sheldon Pennoyer Collection is today conserved at Princeton University.

Following his return to the United States, Pennoyer resumed his career as a successful painter. Later in his career, he became known for his railroad scenes, which were accurately detailed according to the mechanics of locomotion, a subject which deeply fascinated him. He accepted commissions from the Union Pacific Railroad, wrote and illustrated Locomotives in Our Lives (1954), and founded the club, “Railroadians of America.” 

Pennoyer was a member of the American Federation of Arts, the American Watercolor Society, Allied Artists of America, and the American Artists Professional League. Today, his paintings are included in prominent public and private collections, including the Oakland Museum, California Palace of the Legion of Honor, Henry Ford Museum, Metropolitan Museum of Art, Smithsonian Institute, West Point Military Academy, and the De Young Museum.

In June 1957, Pennoyer traveled to Spain to paint watercolors in preparation for a book on Spanish châteaux. He was tragically killed in a car accident near Madrid on August 17,1957.