Yes, Valhalla can be considered a realm within the larger Norse cosmological framework.
Valhalla is more than just a location; it's a distinct hall presided over by Odin and a significant part of the afterlife for chosen warriors. These warriors, known as Einherjar, are selected by the Valkyries to dwell in Valhalla after dying valiantly in battle.
While Valhalla exists within Asgard, the realm of the Norse gods, it functions as a separate entity with its own purpose and inhabitants. It's a warrior's paradise where they train for Ragnarok, the end of the world. This makes Valhalla a unique sub-realm or domain within Asgard.
Therefore, based on its distinct purpose, inhabitants, and cultural significance, Valhalla fits the description of a realm within Norse mythology.
