I often hear about how the vikings discovered America first, but little was done in what was then called Vinland, and the information was lost after a certain period of time. How is that possible? How could a discovery of a brand new landmass which is (at least compared to Greenland and Iceland) hospitable and similar to Nordic climate not have seen more settlement or more information about the region disseminated? How could it's discovery have simply been lost to time? And by far the most confusing to me, how do we know they did this if it was supposedly forgotten (and as a side note, when did we "relearn" this information?)
This is a kind of FAQ about the Vikings, so please forgive me to provides with the cut and paste from the yesterday's thread, Why didn't Columbus/Spain know about Leif Erikson?
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Please also check the following answers either by /u/sagathain, /u/Platypuskeeper, and myself in the following thread:
In short, the news [of the discovery of Vinland] certainly reached also to Scandinavia, and out of Scandinavia in course of the 11th century. The oldest extant written account of Vinland was recorded in the late 11th century Germany.
Nevertheless, these points should be emphasized:
I also wrote a summary about Leif in Can I hear about Leif Erikson, all I know about him is that he was the first important European to step foot in North America and I would like to hear about that and any other cool things he did?.
In short, Leif only appear in two medieval Icelandic sagas, put in writing more than 2 centuries after the original events (the exploration of Vinland) allegedly occurred. I don't say he was entirely invented by the later saga author(s) (there were probably some oral traditions on him also in the 13th and 14th century Iceland), but we are not sure whether he really played an important role in Vinland expedition as the later sagas claimed. At least the oldest written account of Vinland by Adam of Bremen, does not allude to him at all.
As I briefly suggested in Is there any physical evidence of Leif Erickson's settlement on North America?, Leif became really popular (that means to have surpassed the fame of his father, Erik the Red (settler of Norse Greenland settlement)) first in post-medieval times, or it was not until the 19th century that his current popularity originated. His 'fame' of the first European to 'discover' Vinland belongs rather to post-medieval his afterlife to him as a real, historical figure.
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when did we "relearn" this information?
/u/platypuskeeper and I also posted the relevant comments in: