In Canada, the largest Presbyterian denomination – and indeed the largest Protestant denomination – was the Presbyterian Church in Canada, formed in 1875 with the merger of four regional groups. In 1925, the United Church of Canada was formed by the majority of Presbyterians combining with the Methodist Church, Canada, and the Congregational Union of Canada. A sizable minority of Canadian Presbyterians, primarily in southern Ontario but also throughout the entire nation, withdrew, and reconstituted themselves as a non-concurring continuing Presbyterian body. They regained use of the original name in 1939.
Aside from the Congregational Union of Canada, which other church combined to form the United Church of Protestants?