What is Asatru?
Asatru, also known as Heathenry/Heathenism, is a modern revival of the ancient faiths of native Northern Europeans. Unofficially "founded" by Sveinbjörn Beinteinsson in the 70's, Asatru literally translates to "Religion of the Aesir". Information about the original beliefs of the Norse people is difficult to come by as much of the information about them was lost during the Christianization of Europe.
Much of what we know was recorded, and most likely heavily influenced by, Christian scholars.
While the name specifically references the Aesir (war gods), Asatru also honors the Vanir (agricultural gods). These two factions were once at war but came together to rule over the nine realms.
Asatru is a polytheistic system of belief but some of the main gods honored are Odin, Thor, Tyr, Frey, Freyja, and even Loki the trickster god.
Although certainly a modern creation, many Asatruar/Heathens choose to follow the Nine Noble Virtues
Nine Nobile Virtues
The Norse creation myth tells of Odin and his brothers, Vili and Ve, slaying the sleeping giant Ymir to create the 9 worlds.
-Asgard: The land of the Aesir, now home to the "ruling body" of gods. This is where warriors who die gloriously in battle will go to feast and fight in the halls of Valhalla.
-Vanaheim: The land of the Vanir.
-Midgard: The realm of mankind. Connected to Asgard by the rainbow bridge known as "Bifrost"
-Alfheim: Land of the elves.
-Svartalfheim: Land of the dark elves, also known as "dwarves"
-Jotunheim: Land of the giants.
-Muspelheim: Land of fire and chaos.
-Niflheim: Land of primordial ice and mist.
-Hel: Not to be confused with the Christian Hell, this is the Norse underworld where all the dead who did not die gloriously in battle go for their eternal slumber.
All of the realms are held together by the world tree known as Yggdrasil.
There are many interesting creatures inhabiting Yggdrasil itself such as Ratatoskr, a squirrel that carries messages and insults from the serpent gnawing at the roots of the tree to the eagle that rests at it's peak.
Asatru also has it's own doomsday prophecy known as Ragnarok. (Detailed in the Norse poem known as the Voluspa) The watcher god Heimdal will blow his horn to wake the gods. Their enemies, chief among them Loki and his children will break their bonds. They will meet on a battlefield where gods, monsters, and men alike will all perish. In the end the flame giant Surtr will burn all 9 worlds. Only two humans and a handful of gods will remain and the cycle will begin again.