In Norse mythology, which of these is a being who presides over a realm of dead?
In Norse mythology, Hel is a being who presides over a realm of the same name, where she receives a portion of the dead. Hel is attested in the Poetic Edda, compiled in the 13th century from earlier traditional sources, and the Prose Edda, written in the 13th century by Snorri Sturluson. In addition, she is mentioned in poems recorded in Heimskringla and Egils saga that date from the 9th and 10th centuries, respectively. An episode in the Latin work Gesta Danorum, written in the 12th century by Saxo Grammaticus, is generally considered to refer to Hel, and Hel may appear on various Migration Period bracteates.
In the Poetic Edda, Prose Edda, and Heimskringla, Hel is referred to as a daughter of Loki. In the Prose Edda book Gylfaginning, Hel is described as having been appointed by the god Odin as ruler of a realm of the same name, located in Niflheim. In the same source, her appearance is described as half blue and half flesh-coloured and further as having a gloomy, downcast appearance. The Prose Edda details that Hel rules over vast mansions with many servants in her underworld realm and plays a key role in the attempted resurrection of the god Baldr.