The Mennonites are named after Menno Simons, a Dutch priest who was converted to Anabaptism in 1536. The Anabaptists (literally "rebaptizers") were a radical reform movement in sixteenth-century Europe who appeared first in Zurich, Switzerland, among the followers of Ulrich Zwingli in 1525 and soon emerged as scattered communities in central and northern Europe.

The Anabaptists believed that reformers like Zwingli and Luther had not succeeded in bringing about a true reform of the Church. They argued that the Church should be constituted only of those persons who had voluntarily and consciously chosen to follow the example of Jesus and who had received baptism to symbolize that commitment. This interpretation of baptism had significant political implications because territories were defined as either Catholic or Protestant. Since baptism as an infant was the way in which one entered the Catholic Church or a Protestant church, a child born in a territory ruled by a Lutheran prince would be baptized Lutheran whereas a child born in a territory ruled by a Catholic prince would be baptized Catholic. Hence, baptism enrolled the child into the Church and so conferred salvation, and simultaneously enrolled it in the state where that child was born. The Anabaptists insisted that the Church should not be connected with or established by the government, and that baptism should symbolize one’s conscious choice to give allegiance to God’s kingdom rather than to earthly kings or authorities.

Persecution and hardship scattered the Mennonites; some moved east to the regions of Prussia and Poland and from there to Russia beginning late in the eighteenth century. Others, particularly from Switzerland and southern Germany, moved to North America. Eventually many from Russia also came to North America and from there some migrated to South and Central America. All were looking for places where they could establish homes and churches and practice their faith in peace. But the spread of Mennonites from country to country and continent to continent also came about through missions, with the result that today Mennonite churches can be found in 61 countries worldwide, and over 1,000,000 people identify themselves as Mennonites.

Though Mennonites accept the historic confessions of the Church, they also maintain Anabaptist commitments. Mennonites are voluntary believers. Only those who have voluntarily chosen to follow Jesus as disciples are baptized and received into membership in the church. This is called believer’s baptism. Moreover, Mennonites view the Church as the body of Christ, as a community where people live interdependently, care for each other physically and spiritually, and hold each other accountable. Mennonites also believe that faith and action are inseparable and, therefore, they join together to serve the needy in the name of Christ. Many Mennonites accept service assignments ranging from short terms of a few weeks to long terms of several years, working for agencies that seek to alleviate human need. Mennonites believe that following Jesus means conducting all relationships in love and truth, and that violence, killing, and war contradict the way of Christ. Most Mennonites have refused to enlist in the armed services or to defend themselves by force. During wartime, many have chosen to perform alternative service rather than to engage in military service.

-taken from CMU's homepage.