North American English
There are a considerable number of different accents within the regions of both the United States and Canada, originally deriving from the accents prevalent in different English, Scottish and Irish regions of the British Isles and corresponding to settlement patterns of these peoples in the colonies. These were developed and built upon as new waves of immigration, and migration across the North American continent, brought new accents and dialects to new areas, and as these ways of speaking merged and assimilated with the population. It is claimed that despite the centuries of linguistic changes there is still a resemblance between the English East Anglia accents which would have been used by early English settlers in New England (including the Pilgrims), and modern Northeastern United States accents. Similarly, the accents of Newfoundland have some similarities to the accents of Scotland and Ireland.
General American
Though General American accents are not commonly perceived as associated with any region, their sound system does have traceable regional origins: specifically, the English of the non-coastal Northeastern United States in the very early twentieth century. This includes western New England and the area to its immediate west, settled by members of the same dialect community: interior Pennsylvania, upstate New York, and the adjacent "Midwest" or Great Lakes region. However, since the early to middle twentieth century, deviance away from General American sounds started occurring, and may be ongoing, in the eastern Great Lakes region due to its Northern Cities Vowel Shift (NCVS) towards a unique Inland Northern accent (often now associated with the region's urban centers, like Chicago and Detroit) and in the western Great Lakes region towards a unique North Central accent (often associated with Minnesota, Wisconsin, and North Dakota).