From the Global Anabaptist Mennonite Encyclopedia Online (GAMEO):
Fundamentalism came to differing parts of the North American Mennonite world at different times. But for all it was a way of responding to the groups changed relationship to the dominant culture. Fundamentalism among Mennonites was as much an effort to redefine the relationship between culture and Christianity as a crusade to root out theological modernism. It was significantly a cultural movement because the theological modernism in the Mennonite world was only incipient and marginal. Cultural Fundamentalism was a way to codify doctrine, reassert churchly authority and redefine cultural boundaries.
See the full article at http://gameo.org/index.php?title=Fundamentalism