Medieval America?

Okay. Not Exactly.

But could an ambiguously similar society have developed on the eastern coast of North America, in the hypothethical situation that a permanent settlement had been established by transatlantic navigators some centuries before the colonial powers in our timeline?

For example, a Vinland that managed to survive and expand along the coast until it grew so big that splintered into smaller feudal states? Or mayhaps the European nobles managed to escape en-masse from some much more powerful and succesful steppe horde that somehow penetreated into the heartland of their old continent?
 
1) A more successful vinland settlement.
2) Ogedei khan lives 5 to 10 more years. The mongols were perhaps a year or two from overrunning the rest of europe in 1241 when the great khan died.

How it happens
In the last major battle against the mongols in European christendom in 1243, Henry III is killed, his heir is a 3 year old. His wife is deeply unpopular with the barons. Richard of Cornwall the late kings younger brother becomes regent. The retreating english have one brilliant idea....make sure the mongols dont have boats to chase them.


As the mongol hordes turn towards the lands of northern and the riches of Andalusia, the emerging cities of the baltic are full of sailors with ships. The mongol hordes may rule the land but they do not rule the sea. Their ancestral breathren have their Vinland lands to the west and sailors of lubeck, Kiel and Oslo will follow.
 
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