They are probably Mennonites. I was around many of them growing up; Amish too.
Tremendous respect for their beliefs. They truly are of the "You do you; I'll do me" variety and seldome (never?) evangilize or try to impose their beliefs on others, be it town, city, or country.

Further, the Amish have a real unique coming of age custom: the Rumspringa. They are given the option to drop all trappings of Amishness, go out in the world, "do yau thang" and then decide if you want to come back into the fold or not.

In short, unlike other forms of Christianity where once you're in, you're in... the Amish go above and beyond to TRULY make it a person choice and not one imposed on you.