Seymour Fleishman was born in Chicago, Illinois, on January 29, 1918. He attended the Art Institute of Chicago between 1935 and 1941, and then served with the U.S. Army in Australia and New Guinea during World War II, where he was a cartographer and illustrator. After the war, Fleishman returned to Chicago and worked as an artist in the promotional department of the Chicago Sun for three years. He married Esther Marcussen in 1946, and the couple had two daughters.
Fleishman illustrated his first children’s book in 1953. He subsequently illustrated more than 60 other children’s books, including five that he also wrote. Perhaps his most famous illustrations were those of Gus the Friendly Ghost, who was the star of a popular book series by Jane Thayer.
Seymour Fleishman passed away in June 2012 at the age of 94.