Pilgrim Holiness Church or ' International Apostolic Holiness Church '[IAHC] is a religious denomination associated with the holiness movement that split from the Methodist Episcopal Church by Martin Wells Knapp in 1897. It was first organized in Cincinnati, Ohio as the International Holiness Union and Prayer League [IHU/IAHC]. Knapp, founder of the IAHC, ordained and his Worldwide Missions Board sent Charles and Lettie Cowman who had attended God's Bible School to Japan in December 1900. By the International Apostolic Holiness Churches Foreign Missionary Board and the co-board of the Revivalist the Cowmans had been appointed the General Superintendents and the Kilbournes the vice-General Superintendent for Korea, Japan and China December 29, 1905. The organization later became the Pilgrim Holiness Church in 1922 which eventually merged with the Wesleyan Methodists in 1968 to form the Wesleyan Church. Among many other Holiness children, the Korea Holiness Church, daughter of the IAHC/PHC, has approximately 10,000 churches globally and two million members in the four holiness denominations in 2010.
Today, two groups of Pilgrim Holiness churches still exist from the secession of the merger in 1968-the Pilgrim Holiness Church, Inc. (of the Midwest) and the Pilgrim Holiness Church of NY, Inc. These two groups are not associated with the Wesleyan Church today but align themselves with the Conservative Holiness Movement.
The Pilgrim Holiness Church came into being as a result of the revival of scriptural holiness that swept across the various denominations in America in the last half of the nineteenth century, the same awakening that had rechanneled the energies of the Wesleyan Methodist Connection from social and political reform to holiness evangelism. The awakening crystallized in the establishment of many nondenominational and interdenominational holiness unions and associations and independent churches. Toward the close of the nineteenth century many of like faith began to draw together.
A focal point for the beginning of The Pilgrim Holiness Church as an organization was the formation of the International Holiness Union and Prayer League in September 1897, at Cincinnati, Ohio, in the home of Martin Wells Knapp. Rev. Seth C. Rees was chosen President, and Rev. Martin Wells Knapp, Vice-President. The Union was not thought of as a church, nor intended as such, but was an interdenominational fellowship, marked by simplicity and the absence of restrictions. The primary purpose of the Union was to unite holiness people in promotion of worldwide holiness evangelism. A fourfold emphasis was declared concerning the regeneration of sinners, the entire sanctification of believers, the premillennial and imminent return of the Lord Jesus Christ, and the evangelization of the world. The Union met the need of many people for fellowship and cooperation in the spread of scriptural holiness and grew rapidly. Extensive revival work was carried on by members of the Union, resulting in the formation of the many city missions, churches, rescue homes, and camp meetings.