Ralph Carl Wynkoop was born on October 5, 1905, in Omaha, Nebraska, to Sheridan Wynkoop and Louise Katherine Strauss Wynkoop, an emigrant from Germany. Ralph was the fifth of seven children. Ralph died on March 3, 2001, in Kansas City, Missouri.

Ralph was two years old when his family moved to Colorado Springs, Colorado.  They moved to Denver when he was 13.  There the Wynkoop home was within three blocks of the only Church of the Nazarene in Denver at the time and the family was invited to Sunday school before their first Sunday in town. In this congregation Ralph accepted Jesus as his Savior and later was called to preach the gospel.

Ralph served as a pastor in Los Angeles for four years, Ojai, California, for one year, and Marshfield (now Coos Bay), Oregon, for four years. Ralph and Mildred spent the next five years traveling as evangelists, mostly on the West Coast.  They moved to Portland, Oregon, to serve the Brentwood Church of the Nazarene for nine years. When Mildred enrolled in doctoral studies in Chicago, Ralph returned to evangelistic ministry, a service to the Church that continued when Mildred took her first teaching assignment at Western Evangelical Seminary (now George Fox Evangelical Seminary) in Portland, Oregon.

When Ralph and Mildred sailed for Japan in December 1960, Ralph became the pastor of a congregation of American military personnel. He also taught English at the Japan Nazarene Theological Seminary.  When they returned to the United States and Mildred began teaching at Trevecca Nazarene College (now Trevecca Nazarene University) in Nashville, Tennessee, Ralph served as the campus postmaster, but often he could be found functioning as a pastoral counselor to homesick students looking for a letter from family. After ten years at Trevecca, when they moved to Kansas City, Missouri, Ralph worked as the bookstore manager, cafeteria manager, and facilities manager for Nazarene Theological Seminary. In retirement, Ralph preached each Sunday at the Timberlake Care Center in Kansas City.