Heimdall (also spelled Heimdal or Heimdallr), in Norse mythology, one of the Aesir, watchman of the gods, guardian of the heavenly realm of Asgard, and ruler of holy places. His father was the principal god, Odin, and according to the 'Prose (or Younger) Edda', he had not one but nine mothers; they were maidens who were sisters.
Heimdall was handsome, his skin gleaming white and shining. His teeth were made of solid gold. He was also called Hallinskidi, Gullintanni (Golden Teeth), and, when visiting the world of humans, Rig. He was the perfect god to act as sentinel, since he needed less sleep than a bird, and because his senses were very acute: he could see to a distance of a hundred leagues equally well by night or day; he could hear every sound, even the sound of grass growing upon the earth and wool growing on sheep.
Heimdall rode a horse called Gulltopp, and his sword was Hofund (Head). He had a palace called Himinbjorg (Heaven's Cliff) which stood near Bifrost (The rainbow bridge. Bifrost is the bridge that connects Midgard to Asgard. It is guarded by Heimdall. It is made of fire, air and water and these give the bridge its colors, red, blue and green. The bridge can be seen by those in Midgard as a rainbow connecting heaven and earth) , the Rainbow Bridge that connected the realm of the gods (Asgard) to the realm of mankind (Midgard). Heimdall kept watch there to guard Asgard against the encroachment of giants. He owned a trumpet called Gjallarhorn (Clangorous Horn); its blast could be heard to the farthest reaches of the universe. According to legend, Heimdall would be the first god to see the armies of giants and monsters gathering to attack Asgard at Ragnarok, the battle at the end of the world. With Gjallarhorn he would sound the warning of their approach. Despite his responsibilities, Heimdall could be fun-loving; he enjoyed drinking mead in his beautiful banquet hall at Himinbjorg.
Heimdall was the god of brightness and the beneficent uses of fire, and as such stood in opposition to the evil fire god Loki. Loki enjoyed making fun of the diligent watchman, and the two were in constant conflict. In some Norse poetry Heimdall is referred to as the "Foe of Loki." In one tale, Loki stole the fabulous Brisingamen necklace that the goddess Freya had acquired from the dwarfs, and took it out to sea to hide it. But Heimdall, disguising himself as a seal, swam out to retrieve it. Loki then made himself into a seal also, and the two struggled. Heimdall won the necklace back from his devious adversary and returned it to the goddess. During Ragnarok, the battle at the end of the world, Heimdall and Loki were fated to fight to the death, each killing the other.
The Eddic lay 'Rigsthula' recounts how Heimdall was responsible for fathering all Four social classes of people: peasants, farmers and craftsmen, and the nobility. Under the name Rig, he traveled through Midgard, the world of humankind, to see how the descendants of Ask and Embla, the first humans, were doing. Rig came to the poor hut of Ai (Great-Grandfather) and Edda (Great-Grandmother) and though they had little, they were hospitable to the charming god. For three days, Rig ate with them, and at night he slept with both of them. In due course Edda gave birth to a strong son named Thrall, who married a hardworking girl named Esne, and their descendents were all the worlds peasants and laborers. Rig continued his travels and came to a farm where Afi (Grandfather) and Amma (Grandmother) lived, and for three days he ate with them and slept with them. In due course Amma gave birth to a son named Freeman, a builder and blacksmith and farmer, who married a good baker and weaver named Hussif; their children became the world's craftsmen, farmers, and landholders. Rig continued on, meeting Father Squire and Mother Lady, and ate with them in their fine mansion, and slept with them in their luxurious bed. In due course Lady gave birth to a boy named Earl, a hunter and horseman, who married a wealthy, beautiful musician named Princess, and their children became the world's kings and queens. Rig taught Earl secrets of the runes so that he and his offspring could be wise leaders. Then Rig returned to Asgard, well pleased with all his offspring
Heimdall is also a clever god. It was his idea to send Thor to Jotunheim to retrieve Mjollnir from the giant Thrym. (See The Theft of Thor's Hammer for the story). was also known as Rig during his journey to Midgard.