Irish (or Scots-Irish) and German immigrants.
Irish immigrants, often referred to as Scots-Irish because they came through Scotland before the Americas, often arrived in the English colonies as indentured servants or to farm in the Middle Colonies. The Scots-Irish immigrants were often Presbyterian and were looking for a place to practice their faith separate from the mostly Catholic Ireland.
German immigrants came to farm in the Middle Colonies especially Pennsylvania. The community referred to as the Pennsylvania Dutch were actually a community of Germans. This community are mostly Amish and created communities based on a simple lifestyle with farming at the center of their lives.