Robert Norman Munsch was born in Pittsburgh, Pennsylvania. In 1969, he received a B.A. degree in History from Fordham University. In 1971 he received a M.A. degree in Anthropology from Boston University. After graduating, he studied to become a Jesuit priest, but his experiences in orphanages and day care centers led him to decide he would rather work with children. In 1973, he received a Master of Education in Child Studies from Tufts University. In 1975 he moved to Canada to work at the preschool at the University of Guelph in Guelph, Ontario. He also taught in the Department of Family Studies at the University of Guelph as a lecturer and as an assistant professor. In Guelph, he was encouraged to publish the many stories he made up for the children he worked with. His first book, Mud Puddle, was published in 1979.
After his wife delivered two successive stillborn babies, he wrote his most famous book, Love You Forever (1986). He and his wife have since adopted three children.
In August 2008, Munsch suffered a stroke that affected his speech. To date, he has written over 50 children's books.
