Frank E. Schoonover was born August 19, 1877 in Oxford, New Jersey. His family settled in Trenton, New Jersey near the Delaware River.  As a youth he spent part of each summer with his grandmother in Bushkill, Pike County, Pennsylvania, where he was attracted to the surrounding fields and streams and some of his earliest memories and drawings were of those subjects. In 1891, he graduated with high honors from high school in Trenton, New Jersey, where he gave the salutatory address. After considering the idea of entering the ministry, he decided, in 1896, to attend art school at the Drexel Institute in Philadelphia where he studied under Howard Pyle, who eventually became a friend and confidant.

Schoonover went on to win one of the ten prestigious scholarships to the Chadds Ford Summer classes in 1898 and 1899 where Pyle tutored the most advanced students. Under Pyle's encouragement he was soon illustrating books, many of the themes heavily influenced by his love of the outdoors. When Pyle left Drexel to build his own school, Schoonover went with him. In 1903, Schoonover spent four months exploring the Hudson Bay and James Bay areas of Quebec and Ontario on foot and by dogsled. This experience turned out to be the inspiration for some of his best work throughout his career, including a series of illustrated stories for Scribner's Magazine in 1905.  From then on he never missed an opportunity to travel from the studio in his quest to absorb atmosphere and local colour: Virginia, Colorado, Montana, Louisiana, Jamaica, etc. Also in 1905 he had his first fiction published and became a member of the Society of Illustrators. 

In 1906, he left Pyle's school to open his own studio in Wilmington, Delaware at 1305 Franklin Street and later at 1616 Rodney Street, which was to become home base for the rest of his life. He married Martha Culbertson of Philadelphia in 1911. From 1903 to 1913 he did illustrations for all the major magazines of the day (Harpers, Ladies' Home Journal, Scribner's, Century, McClures), and soon became recognized as one of the country's premier illustrators. He continued his association with Pyle until the master's death in 1911 - together they worked on the Hudson County Courthouse Murals. Besides doing magazine illustration, Schoonover wrote articles and stories and illustrated more than two hundred classics and children's books. Throughout his career he illustrated the works of many famous authors: Edgar Rice Burroughs, Jack London, Rex Beach, Zane Grey, Robert W. Chambers, Gilbert Parker, Henry Van Dyke, Clarence Mulford, etc. 

He and Gayle Hoskins organized the Wilmington Sketch Club in 1925, and in 1931 he lectured at the School of Illustration for the John Herron Art Institute of Indianapolis. In the late 1930s after the decline in the popularity of illustration, Schoonover devoted himself almost exclusively to landscape painting, mainly landscapes of the Delaware and Brandywine River valleys. He was back to the fields and streams that had fascinated him as a youth. In 1942, he started his own school in Wilmington which lasted almost 25 years. Schoonover, a devout Episcopalian, devoted much energy to Immanuel Church, Wilmington, where he designed 16 stained glass windows and served as warden for 41 years until 1959. After a series of paralyzing strokes, which ended his artistic career in 1968, Schoonover died at the age of 95 in 1972.

Schoonover's subject matter covered a broad spectrum but he seemed most at home with frontier and adventure themes and rugged landscapes. His forms were simple and well defined and his moods powerful. Later in his career, his style became less rigid and more impressionistic. Schoonover was also an accomplished watercolorist and muralist and an avid photographer.