 Harper was born in Turtle Creek, Pennsylvania, near Pittsburgh, the son of George Harper and Mabel Grace (Champion) Harper.Harper became valedictorian of his senior class and won an academic scholarship to Princeton University in New Jersey, where he supplemented his academic studies by performing in a number of plays and musical comedies, before relocating to New York City, where he studied with Lee Strasberg.After serving in the US Navy, Harper returned to New York.