Shortly after the formation of the United Church of Canada, Charles Clayton Morrison told readers of the Christian Century to “put down a new monumental date in ecclesiastical history—Wednesday, June 10, 1925.” “On that day,” he continued, “took place the first large scale achievement of organic union of separate denominational families since the Protestant Reformation.” Aware that the full significance of this venture would not be evident for some time, he predicted it would be “the object of continued study and exposition for months and perhaps years to come.”1 Since Morrison's enthusiastic pronouncement, a considerable body of literature has accumulated on the church union movement and the United Church of Canada. No critical evaluation, however, has been made of it and little is known about its authors or their understanding of the formation and development of this Canadian institution.