Leslie Arden Dunn was born in Kansas City, Kansas on September 8, 1907, and spent his early boyhood in Osawatomie, Kansas. He made the promises of Christ his own shortly after his family moved to Milwaukee, where he worked on the railroad and attended Milwaukee West High School. He became active in the Christian Endeavor Union, serving as its president. Though money was scarce, he attended Wheaton College in Wheaton. Illinois, sometimes working up to 70 hours a week to support his education. He graduated from Wheaton in 1932, and, thanks to a free ride to Philadelphia arranged by J. Oliver Buswell, he arrived at his seminary of choice, Westminster Theological Seminary in Philadelphia, Pennsylvania. He was the beloved pastor of Presbyterian Church USA congregations in Columbus, NJ, and Wrightstown, NJ, and Orthodox Presbyterian congregations in Trenton, NJ, Wildwood, NJ, Westfield, NJ, Portland, ME, and Tinley Park, IL. He served for 33 years with the Committee on Foreign Missions of the Orthodox Presbyterian Church, for 10 years on the Committee on Christian Education of the Orthodox Presbyterian Church, and for 10 years as the Executive Director of the Boardwalk Chapel in Wildwood, NJ, a work he founded. His pastoral gifts were used long after his formal retirement at Falls Presbyterian Church in Menomonee Falls. He has been a beloved member of this congregation for many years.
Pastor Dunn's first wife, Inez, died when their daughter, Karin, was six years old. He met a lively young lady, Margaret Hunt, working at the Christian Education offices of the Orthodox Presbyterian Church in Philadelphia. He soon won her heart and they were married on May 11, 1946.