The heartland for Iroquoian languages is in the Allegheny plateau. Migrations at various points in history spread Iroquoian-speakers as far north as modern day Montreal and as far south as the Great Smoky Mountains by the time of European contact. Cherokee seems isolated from the Iroquoian populations of the north people many of these highland societies are poorly known outside of archaeological circles. The Susquehannocks (along the eponymous Susquehanna River) were the main Iroquoian population in eastern Pennysylvania, but were defeated and absorbed into the Haudenosaunee (the Iroquois Confederacy by the 1700s). The Monongahela / Massawomeck appear to have been the most prominent Iroquoian society in southwestern Pennsylvania / northern West Virginia, but appear to have collapsed around 1635 when the first major wave of introduced epidemics entered the Ohio Valley. They had little contact with Europeans prior to this so they were poorly recorded in colonial histories. Further south you get the Tuscarora, the Nottaway, the Cherokee, among others. The southern groups tended to be much smaller and more de-centralized than their northern counterparts, at least until the Cherokee ascent began in the 1600s.

As for Algonquian, we first need to take a step back. Linguistically, Algonquian is the largest subdivision of the Algic language family. The languages you noticed in California are non-Algonquian Algic languages. The current theory is that the Algic homeland was originally in the Columbian Plateau region. A disruption in the area forced the Algic-speaking peoples out, with some heading west into Calfornia and others heading east onto the northern plains. Those that headed east became the Algonquian-speaking peoples. Of those, Blackfeet seems to the earliest language to diverge from the rest, hinting that they may have lingered behind on the plains while others continued to migrate eastward. There appears to have been a standstill north of the Great Lakes, based on commonalities in words related to specific plants that grow in that region, before a more recent wave of migrations sent Algonquian-speaking into the Ohio Valley and East Coast. Finally, more recent, historic migrations sent groups like the Cheyenne and Arapaho out of the western Great Lakes and across the Plains.