Valhalla and Folkvangr are two significant realms in Norse mythology that serve as afterlives for warriors who die in battle. Valhalla, ruled by Odin, is a majestic hall where chosen warriors, known as the Einherjar, gather to feast and prepare for Ragnarok. Folkvangr, on the other hand, is ruled by the goddess Freyja and serves a similar purpose but is often associated with different qualities of valor and honor. Both realms highlight the Norse culture's reverence for bravery and the warrior ethos.