Persecution forced Menno Simons to leave the Netherlands and settle in northern Germany. However, his focus still remained on the Netherlands. His influence in the Netherlands was so widespread that at least until the early 1560s there were more Mennonites than Calvinists in the Low Countries. 

Mennonite beliefs were largely shaped by Simon’s emphasis on spiritual regeneration, the pure church, and the ongoing experience of religious persecution they faced in the Low Countries. Like other Anabaptists Mennonites believed in the importance of sanctification and spiritual growth. Simons also believed in radical discipleship which consisted of fellowship with a spotless congregation set apart from worldly influences. This congregational purity was enforced through admonition and in extreme cases banning or shunning. The purpose of banning and shunning was to shame the sinner into remorse and reconciliation with the community. 

To a great extent, the self-imposed isolation from the world enforced by the Mennonites was shaped by the persecution they faced. They felt they were defenseless in the face of the bloodthirst pursuit of the Catholic ecclesiastical authorities as well as the various political authorities of the states they lived in.