Pennsylvania Amish

http://theamishvillage.net/lancaster-county-amish
http://www.padutchcountry.com/towns-and-heritage/amish-country/amish-history-and-beliefs.asp

The Pennsylvania Amish situated in Lancaster County have a history that dates back to the 18th century and to the time of William Penn's promotion of religious and cultural freedom. A small Amish community from Europe came and settled at this time, and since then, the Amish have stuck with the traditional way of life from 300 years ago, with farming and a simplistic, non-materialistic attitude creating their lifestyle (with electricity being banned as it creates too much of a connection to the outside world). They (as well as the Mennonites and Brethren in Lancaster County) are of the Anabaptist faith which means that they make a conscious choice to accept God and their devotion to God is therefore incredibly evident.
All Amish, not just the Pennsylvania Amish have similarities in their views of humility, family, conservatism, community and therefore live separately from the non-Amish community in order to achieve this effectively. However, an aspect of the Lancaster County Amish is that they are expected to give up their personal aspirations in order to create a 'pure' community.
Their style of dress promotes a sense of group belonging and identity, whilst demonstrating the willingness to give themselves in to group standards. The male clothing of the Pennsylvania Amish is black and consists of a dark suit, suspenders, straight cut trousers, black shoes and a black or straw hat. They wait until marriage to grow beards. Whereas Amish women wear plain, long sleeved dresses, a cape and an apron. They never cut their hair and wear it in a bun covered by a prayer covering.
Pennsylvania Deutsch (a dialect of German) is spoken, therefore limiting outside interaction even further and the children learn English in school but German for worship services.