Indiana Apostolic Holiness Church -1914

Formed through the merger of several smaller Holiness denominations—many of which had undergone multiple name changes over the years.

Origins (1897–1900):
The foundation of the movement began in 1897 with the creation of the International Holiness Union and Prayer League by Rev. Martin Wells Knapp and Rev. Seth C. Rees in Cincinnati, Ohio. This organization was committed to promoting holiness and revivalism through literature, missionary associations, and evangelistic efforts. By 1900, the name was changed to the International Apostolic Holiness Union to emphasize a return to apostolic Christianity.

Expansion and Structure (1900–1913):
As the movement grew, it expanded its reach by establishing missions, churches, rescue homes, and schools. Missionaries were sent to various regions across the globe, including Africa, India, Japan, the West Indies, and South America. In 1905, the organization adopted the name International Apostolic Holiness Union and Churches, reflecting its shift toward a more defined denominational structure. By 1913, it became known as the International Apostolic Holiness Church.

Mergers and Growth (1919–1922):
Significant growth occurred through a series of mergers. In 1919, the Holiness Christian Church, which originated in Pennsylvania in 1882, merged with the International Apostolic Holiness Church to form the International Holiness Church. This was followed in 1922 by the addition of the Pentecostal Rescue Mission of New York (founded in 1897) and the Pilgrim Church of Pasadena (founded in 1917), at which point the name Pilgrim Holiness Church was adopted.