Haudenosaunee Republic (1983: Doomsday)

The Haudenosaunee Confederation, or Iroquois Confederation is a confederated republic located in upstate New York, founded by the remnants of the Iroquois people and refugees from cities such as Syracuse that fled south rather than north. It is bordered by the Republic of New York to the south, and the New York Rangers Protection Zone to the southeast.

Pre-Doomsday:
The area where the Confederation would later administrate was once part of a large apple farming region. In fact, a variety of apple, the Cortland, was named after a county in the region. Light industry and other forms of farming also were important to the region. The Iroquois people, specifically the Onondaga and Cayuga inhabited this region, and continued to do so, although their numbers were greatly eclipsed by white settlers.

Doomsday:
On Doomsday, the nearby city of Syracuse was struck, destroying a major metropolitan area, and sending fallout into the area nearby. The Onondaga Reservation, directly south of the city, was also affected by the blast, though not completely. The area south was also lucky, as fallout also mostly missed the area, as the winds were heading northeast, and the blast was not large enough to destroy some of the southern suburbs of the city. (Source here, and here.)