why couldn't the vikings hold on to Canada?

Climate change actually.

The Viking colonies got cut off from their supply chain by a few decades of very harsh weather. They were just unlucky enough to land and try to set up in north America right before the earth went into two decades of very harsh weather in that region, cutting them off from help and supplies, and it is what killed them, it is what might kill the rest of us too if we are not careful.

Those who know anything about the history of vikings, know that if the weather had been on their side, they would have been able to colonize north America first (and possibly flourish)

P.s. the guy who said; The Vikings were forced out by the locals, and the crops they liked just wouldn't grow in Canada. Has no historical idea of what he is talking about.

The Vikings were forced out by the locals, and the crops they liked just wouldn't grow in Canada.

BTW, the Italians (Romans) were great at colonization. Which is why in this conversation, about half the words or more are Latin in origin.

It was a question of numbers. One boatload of Vikings couldn't outnumber several thousand Natives.

A combination of hostile natives and harsh Winters,the latter of which meant game was scarce for several months of the year,and thus food was often in short supply.