Arda is a terrestrial world, thought by most to lie within a parallel material plane known as the Plane of Eä. Arda and its plane is ruled and shaped by the creator deity Eru Ilúvatar, possessor of the Flame Imperishable. Rifts occasionally connect Eamon and Arda, and individuals are known to have crossed between the two worlds.
Arda's largest continent, Middle-earth, is inhabited by many of the same races as Addar including humans, halflings, elves, dwarves, orcs, dragons, and others, and some scholars suggest shared cultural and hereditary connections.