What is the in universe relationship between the Asgardians and Nordic cultures?

Question

In real life Nordic mythology, Thor and Odin are deities, similar to the Greek gods or the Roman gods.

In the MCU and other Marvel media, Thor, Loki, Odin, and other Asgardians are occasionally referred to as gods, but it is clear that they are just extraterrestrials who happen to be a lot stronger, have more abilities, and live a lot longer than the average human.

I always assumed that the in-universe explanation for why the Nordic people named their deities after them was that there was some contact between ancient Scandinavian civilizations and the Asgardians, but I can't find any references to how or when that contact actually happened. All the stories seem to start with Thor's present-day banishment to Midgard.

So what is the in-universe explanation of what the relationship is between Nordic culture and Asgard? Did Thor, Odin, etc...actually visit Scandinavia during ancient times?

Answer 1

To answer your question, there were many incidents of contact between Earth and the Asgardians centuries before the events of the first Thor. According to the ambiguously canonical Thor junior novelization:

Midgard, also known as the Planet Earth, has long captured the interest of the Asgardians, who have traveled on the Rainbow Bridge to observe this realm.

The exact reason as to why this is so is not clear. I theorize that it may have to do with the initial desire by Odin and Hela to conquer the Nine Realms. They formed a strong relationship with humankind, teaching the Norse people specifically their language and culture. In return, they were worshipped as gods. A few notable events happened that led to this:

• Jotunheim-Asgard War (not official name) - In the tenth century, the Frost Giants also set out to conquer the Nine Realms, including Earth. Presumably because of their relationship with humans, the Asgardians (led by Odin) set out to defend Earth. Eventually this led to a truce after Jotun king Laufey surrendered in 965 AD.
• Berserker Army Incursion - In the twelfth century, a group of Asgardians known as the Berserker Army came to Earth and left a Berserker Staff, a weapon that provided them with immense power. One warrior stayed, later becoming known as Elliot Randolph, and hid the staff.

Eventually, the Asgardians stopped coming to Earth, allowing their name to become legend to the Nordic people.

Sources: Thor, Thor: Ragnarok, Agents of Shield: Season One, Episode Eight: "The Well"