By the 1960s, hundreds of small ethnic private schools had proliferated across Canada. Using a mix of archival sources and oral histories, this article examines the founding and transformation of Westgate Mennonite Collegiate, a school formed in 1958 by Mennonites in Winnipeg, Manitoba. The particular definition of ethno-religious identity (Mennonitism) that the school attempted to inculcate in students differed from that promoted by other Mennonites in the province, and also changed over time. As a result, the school's history – and possibly the history of other similar schools – defies simple categories of assimilation or cultural resistance. More such oral and institutional histories are necessary to illuminate the role these hundreds of ethnic private schools have played in the story of Canadian multiculturalism.