As you will know, humanity has taken great length of understanding where we came from. As humanity spread out from the centers of Africa, groups because separate cultures and they all started to teach their youngs different stories on how the world was as they saw at that time.
One of those creation myths (as we know that gods didn’t make life), is from the age of Vikings (or most likely before). We could reiterate the full story here (and likely we will do in the future, but for now, we leave you with a well documented version elsewhere: