From 1948-62, the family lived in West Germany, before moving back to the United States. After studying at Clongowes Wood College (a Jesuit school in Ireland) from 1955–61, he attended the University of Tübingen (Walsh spoke fluent German), and then the University of Rhode Island, where he starred in many college theater productions. In 1974, he was discovered by a theatre Director and began working in off-Broadway shows. After college Walsh worked briefly as a VISTA volunteer in Newport, Rhode Island organizing tenants for the United Tenant Organizations of Rhode Island (UTO) before resigning to pursue his acting career.