Thor is the Norse god of thunder. He is a son of Odin and Jord, and one of the most powerful gods. He is married to Sif, a fertility goddess. His mistress is the giantess Jarnsaxa ("iron cutlass"), and their sons are Magni and Modi and his daughter is Thrud. Thor is helped by Thialfi, his servant and the messenger of the gods.
Thor was usually portrayed as a large, powerful man with a red beard and eyes of lightning. Despite his ferocious appearance, he was very popular as the protector of both gods and humans against the forces of evil. He even surpassed his father Odin in popularity because, contrary to Odin, he did not require human sacrifices. In his temple at Uppsala he was shown standing with Odin at his right side. This temple was replaced by a Christian church in 1080.
The Norse believed that during a thunderstorm, Thor rode through the heavens on his chariot pulled by the goats Tanngrisni ("gap-tooth") and Tanngnost ("tooth grinder"). Lightning flashed whenever he threw his hammer Mjollnir. Thor wears the belt Megingjard which doubles his already considerable strength. His hall is Bilskirnir, which is located in the region Thrudheim ("place of might"). His greatest enemy is Jormungand, the Midgard Serpent. At the day of Ragnarok, Thor will kill this serpent but will die from its poison. His sons will inherit his hammer after his death.
Donar is his Teutonic equivalent, while the Romans see in him their god Jupiter. Thursday is named after him.