I was just thinking up a story for an event where a Micmac king goes to the Vinland king and appeals for aid in a war against the Huron. It would go something like this:
(From the perspective of Vinland)
The great king -fill in space here- of the mighty kingdom of Vinland, sat solemnly as he listened to the words of the Micmac chieftain, who himself travelled on an errand of great urgency. "My friend, our people, who have stood by your's in the great Beothuk war of ages past; now ask for your help in defending us against our enemies, the Huron. We celebrate our mutual victory in songs. Have you now forgotten how great our alliance once was?" These were the words of the Micmac chieftain -fill in space here-, as recorded by an observor to this meeting. The Norse king still sat solemnly, but began to speak...
And then of course here would be choices of whether to support them, remain neutral, etc...
It makes it known that peaceful relations existed with the Micmac long before 1419, as hinted by the reference to the great Beothuk war.
We could even make the argument that it was the Micmac's help which allowed the Vinlanders to gain complete control of Newfoundland from the Beothuk. And that without the Micmac's help the Vinlanders would have been wiped out as was historically the case... This story I think would help explain why the relations between the two are so close at game start.