 After graduating from the College of the Holy Cross and unsuccessful attempts at law school and writing novels, O'Callahan found his voice as a professional storyteller in the 1970s, one of the early proponents of what has been called the American Storytelling Renaissance.He came to national prominence in 1980 with his first appearance at the National Storytelling Festival.In 1996 he was inducted into the Circle of Excellence by the National Storytelling Association (now National Storytelling Network).