In Germanic mythology, Thor (/θɔːr/; from Old Norse: Þórr) is a hammer-wielding god associated with thunder, lightning, storms, oak trees, strength, the protection of mankind and also hallowing and fertility. Besides Old Norse Þórr, extensions of the god occur in Old English as Þunor and in Old High German as Donar (runic þonar ᚦᛟᚾᚨᚱ). All forms of the deity stem from a Common Germanic *Þunraz (meaning thunder).
Thor is a prominently mentioned god throughout the recorded history of the Germanic peoples, from the Roman occupation of regions of Germania, to the tribal expansions of the Migration Period, to his high popularity during the Viking Age, when, in the face of the process of the Christianization of Scandinavia, emblems of his hammer, Mjölnir, were worn and Norse pagan personal names containing the name of the god bear witness to his popularity.
Due to the nature of the Germanic corpus, narratives featuring Thor are only attested in Old Norse, where Thor appears throughout Norse mythology. Norse mythology, largely recorded in Iceland from traditional material stemming from Scandinavia, provides numerous tales featuring the god. In these sources, Thor bears at least fifteen names, is the husband of the golden-haired goddess Sif, is the lover of the jötunn Járnsaxa, and is generally described as fierce eyed, red haired and red bearded. With Sif, Thor fathered the goddess (and possible valkyrie) Þrúðr; with Járnsaxa, he fathered Magni; with a mother whose name is not recorded, he fathered Móði, and he is the stepfather of the god Ullr. By way of Odin, Thor has numerous brothers, including Baldr. Thor has two servants, Þjálfi and Röskva, rides in a cart or chariot pulled by two goats, Tanngrisnir and Tanngnjóstr (that he eats and resurrects), and is ascribed three dwellings (Bilskirnir, Þrúðheimr, and Þrúðvangr). Thor wields the mountain-crushing hammer, Mjölnir, wears the belt Megingjörð and the iron gloves Járngreipr, and owns the staff Gríðarvölr. Thor’s exploits, including his relentless slaughter of his foes and fierce battles with the monstrous serpent Jörmungandr—and their foretold mutual deaths during the events of Ragnarök—are recorded throughout sources for Norse mythology.
Into the modern period, Thor continued to be acknowledged in rural folklore throughout Germanic-speaking Europe. Thor is frequently referred to in place names, the day of the week Thursday bears his name (modern English Thursday derives from Old English Þūnresdæg, ‘Þunor’s day’), and names stemming from the pagan period containing his own continue to be used today, particularly in Scandinavia. Thor has inspired numerous works of art and references to Thor appear in modern popular culture. Like other Germanic deities, veneration of Thor is revived in the modern period in Heathenry.