Henry Smith Leiper was born in Belmar, New Jersey in 1891, the son of Joseph McCarrell Leiper and Fanny Smith Leiper. Joseph Leiper worked for the Dodd, Mead publishing company, but left his job to attend Union Theological Seminary. Fanny Leiper was a music and arts teacher and the daughter of a Massachusetts legislator. Leiper's parents moved in 1889 to what would become Oklahoma to do mission work, and Joseph Leiper was eventually ordained in the Territory. Fanny Leiper died in 1895, and Leiper and his two brothers were raised by other members of the family including several aunts. Leiper moved frequently, but settled for some years with his grandmother in Worcester, Massachusetts. He studied at Maryville College in 1905, a preparatory school in Knoxville, Tennessee, and from there went to Blair Academy in New Jersey, where he spent three years. Leiper earned a B.A. from Amherst College in Massachusetts in 1913, where he got deeply involved in the Student Volunteer Movement (SVM). He planned for a career as a missionary, and moved to Union Theological Seminary in 1913. He withdrew to work for the SVM, drumming up support around the country, but he returned to Union in 1914 to prepare for the ministry. He studied under Harry Emerson Fosdick. Leiper eventually transferred his credits to Columbia towards an M.A. in Philosophy and Ethics, which he received in 1917. Leiper began his missionary work in China in 1918, where he and his family (which by now included a wife and two young children) settled into the missionary routine of preaching, teaching, and community service. Leiper's work took him beyond China, and he spent some time traveling elsewhere in Asia, including Japan and Siberian Russia. Leiper spent much of his time working with students in China, a continuation of his own interest in the SVM. In 1921, Leiper was elected by the North China Mission as Mission Auditor, Chairman of the Mission Property Committee, and as a delegate to the Japan Mission meeting. His work in Japan particularly disturbed some members of the Mission, who felt Leiper was too critical of the performance of the Japanese Mission. The Leipers returned to the United States in 1922 when Mrs. Leiper became too ill to remain overseas. The bulk of Leiper's professional career was spent working in various organizations. He served as secretary for numerous groups including the Congregational Commission on Missions from 1923-1930, the American Missionary Association from 1924 to 1927, and the Federal Council of Churches from 1930 to 1945. Leiper was also active in movements that did not necessarily have official organizations. He was an outspoken critic of the Nazis in Germany, and preached against Germany's aggression in churches around the world. Leiper concentrated particularly on Nazi tactics against religion and religious figures. Leiper's activities were often dangerous, and he had to resort to circumspect arrangements to avoid attracting attention. He was part of a group that attempted (unsuccessfully, as it turned out) to initiate a U.S. boycott of the 1936 Olympic games in Berlin. Among Leiper's other great accomplishments was his involvement in the creation of the World Council of Churches (WCC), an outgrowth of looser international ecumenical ties of the 1930's. The group began at the Utrecht Conference of 1938, and Leiper was elected Associate General Secretary. The war interrupted the earliest plans of the group, but after 1945 the WCC was able to expand its activities throughout the world. Leiper worked on refugee projects, Bible distribution, and a great deal of speaking in the name of Christian unity. His major contribution, however, was in the area of fundraising. He was responsible for the bulk of the funds raised in the U.S., especially the money raised for the WCC Conference in Amsterdam in 1948. Personal conflicts with the head of the WCC, W.A. Visser 't Hooft, and other members of the organization eventually led to Leiper's leaving the international job for a purely American post with the New York office in 1948. Tensions continued, however, and Leiper left the WCC for good in 1952. Leiper went back to work for the Congregational Church for the next several years, serving as Executive Secretary of the Missions Council. He held that post until 1959, when he retired from activity in organizations. Leiper did not remain inactive, however, as he took the post of Director of the Religion Department at Chautauqua College in New York. He moved from Chautauqua in 1967 to the American Bible Society, where he served as an advisor. Leiper's family was small but well-knit. He married Eleanor Lansing Cory in 1915, and the couple had two children, Juliet McCarell (known as Carell) in 1916 and Henry Martyn (known as Hal) in 1918. Eleanor Leiper shared her husband's interest in the missionary movement (the two met at an SVM summer Bible camp) and worked on projects of her own, particularly in China. The illnesses that forced the family's return to the U.S. in 1923 eventually took their toll, however, and she died in 1935. Leiper was remarried that same year to a family friend, Elizabeth Glover Olyphant. Misfortune struck the family again in 1960, when son Hal died of cancer. Besides his work, Leiper was fascinated with both music and mechanical objects. He played piano and organ for many years, occasionally professionally. He designed the family's house in China, and spent several of his transatlantic crossings in the mechanical rooms of the ships. Henry Smith Leiper died in 1975 at the age of 83.