John Maclean (spelt McLean until 1890) was born in Kilmarnock, Scotland on October 30, 1851 to John and Alice McLean. He came to Canada in 1873 and in 1875 was accepted on a trial basis as a minister of the Methodist Church of Canada. A lifelong learner, Maclean enrolled at Victoria College in Cobourg and earned a BA (1882) and a MA (1887) before earning his PhD in church history from Illinois Wesleyan University in Bloomington in 1888 and his LL.B from the University of Manitoba in 1926.

Maclean married Sarah Anne Barker on June 10 1880 in Guelph, Ontario. The newlyweds left soon after for a new Methodist mission near Fort Macleod, Alberta. They spent nine years living among the Blood Indians, learning their languages, customs and traditions. He received mixed reactions from the Aboriginals; some accepted his contributions of food and education, while others damaged his property. Maclean had a sincere interest in Aboriginal culture and was considered an expert in the field – he corresponded with many ethnologists as well as the Bureau of Ethnology of the Smithsonian Institution in Washington, D.C., about the languages and literature of the Aboriginals in the west. He wrote extensively about the Aboriginal people in Western Canada. What set Maclean apart from many missionaries and academics at the time was that he treated Aboriginal people as humans.

Maclean accepted an appointment with the Board of Examiners for Teachers in Moose Jaw in 1889 and was also the first cleric to serve the Wesley Church. His family lived in Moose Jaw until 1892. They moved to Port Arthur, Ontario (1892–95), Neepawa, Manitoba (1896–1900), and Carman, Manitoba (1901–2). He lived in Halifax as the editor of the Wesleyan from 1902-1906, and was stationed in Morden, Manitoba until 1911. In 1911, Maclean and his wife were sent to help the Bethel mission in Winnipeg and worked there until 1919.

In 1918, Maclean was appointed to the chief archivist position at the Methodist Church at Wesley College, Winnipeg. He held this position along with with that of chief librarian from 1922 until 1928. He died March 7, 1928 in Winnipeg.

Maclean, John / Dictionary of Canadian Biography Online