Well, Vinland wasn’t the frozen north at that time. That’s why they called it “Wine-land”, because grapes were growing in Northern latitudes during that time.
Did they teach the native northern tribes about long houses and fort walls? I think they traveled further inland than they are given credit for. (Before the Italian/Spanish and English arrived.)Hmmmmmmm? Did native tribes with blue eyes exist?
I’ve read that the reason the Greenland colony failed was due to increasingly colder seasons. This yielded shorter and shorter growing seasons and the colony couldn’t sustain itself on fishing alone. It was finally abandoned at about the same time that Columbus was getting organized.