No one knows the exact date of composition of the Poetic Edda. No one can even tell if it's a single authorship or a collaboration of two or more writers. This collection of old poems is about Norse mythology, and it has been the basis of some of the enduring works in popular culture.
Some would insist that Greek mythology is more popular, and they're right. In fact, Rick Riordan must be commended for the public's renewed interest in the Olympian deities and the demigods. If not for Percy Jackson, Zeus might not ring a bell anymore. Not Odin (unless they're diehard fans of Marvel Studios). Not if they know the Marvel Cinematic Universe (MCU).
"Ant Man" marked the end of the second phase of MCU. It will be an exciting time for those who are up to date with the franchise, as the third phase will introduce new superheroes and the latest from the more established characters (with superhuman powers). One of which is the Norse version of the Apocalypse. But we're getting ahead.
If you're still in the dark about Norse mythology, then it's time to get to know more of it. (Riordan would be a big help, as the first book of the Magnum Chase trilogy was out last October. It's about the Norse myth, in case you don't have a clue.) Here are three reasons:
You don't need to fly to Scandinavia. Unless you want the real thing, then you only have to look for the most popular works in Norse myth. For instance, Dik Browne's HÃ¤gar the Horrible took place during the Viking Age. It happened during the early part of the Middle Age. The comic strip depicted Scandinavian life in an amusing light, with the titular character wanting to plunder distant lands. It seemed strange, but that was really the case. (The most urbanized communities were found within the Roman Catholic Empire.) It was troubled times. (This had been the case after the decline of an empire.) Not many have a clue about Thor. Nonetheless, these were slices of a culture that once flourished in Europe. Who would have thought that they would be the most progressive society in the modern era.
Thor and company are as interesting as their Greek counterparts. Only those who have read too many Marvel comics and Neil Gaiman's books can attest to it. There's a wealth of exciting tales in Norse mythology, which is still untapped. Edith Hamilton have written a few chapters in "Mythology". Whether or not Riordan will do another series remains to be seen. It requires serious research.
Norse mythology will leave you breathless. Asgard is one of the Nine Worlds unified by the Yggdrasil. Anyone familiar with Thor and his whereabouts have an idea about Asgard, but the other realms are foreign lands. It would be up to you to find out.