As a community, the Amish feature some level of differentiation. There research to suggest that geography is part of this. The Amish who live in Pennsylvania are a part of the general Amish community found in Ohio and Indiana and Canada, yet they are each isolated and governed by lay leadership in the community. Lancaster County in Pennsylvania is home to some of the oldest generation of Amish. The same challenges of seeking to navigate the balance between religious traditionalism and modernity beset the Amish in Pennsylvania as they do in Ohio and Indiana.
Geography does define religious differences in the Amish culture and it does define cultural differences between different districts of Amish communities. Geographically speaking, there are many significant differences between what is acceptable from one church district or affiliation of Amish people to another. Distance from each other is an important factor creating isolation and allowing various lay leaderships to make divergent choices.
There are many different affiliations of Amish, each of which has its own dress styles, carriages, occupations, and rules about technology. The enormous cultural diversity among Amish groups and church districts makes it risky to generalize about “the” Amish. (Young Center for Anabaptist and Pietist Studies, Elizabethtown College)
The relationship with the "outside" world might play a more significant role in cultural definition. For example, the Amish in Lancaster County struggle with how to assert their own sense of identity in the midst of a tourism trend that has turned out to be a big business. The weight of expectation is something that can be seen in the Amish community as playing a critical role in definition of self and in forming their own definition to the outside world.
Geography and choices about interactions with the "outside" world through seeking to find valences of navigation in asserting their own sense of self in a world that is vastly different from them both play significant roles in creating differences between Amish groups, affiliations and church districts.