Why 4 Days of the Week Are Named After Norse Gods

The god of war and justice, Týr is regarded as the Norse equivalent of the ancient Roman god Mars. 

Renowned for his courage and sense of honor, Týr is best remembered for sacrificing his right hand to bind the monstrous wolf Fenrir. According to mythology, the gods feared a prophecy that foretold Fenrir would one day kill Odin—the ruler of the Norse gods—and help bring about Ragnarök, the apocalypse. After the wolf repeatedly broke free from increasingly strong restraints, he grew suspicious of the gods' intentions. Fenrir agreed to be bound only if one of the gods placed a hand in his mouth as a pledge of good faith.

“Týr had been feeding Fenrir, so stepped up and put his hand in his mouth,” says Carolyne Larrington, author of The Norse Myths: A Guide to the Gods and Heroes. “They put this magic ribbon made by the dwarves out of things like the beard of a woman, the breath of a fish, the roots of the mountain and various other things around his legs," she explains. "Fenrir struggles and it tightens like iron. Realizing he’s trapped, Fenrir bites off Týr’s hand.”

Ultimately, the prophecy comes true. During Ragnarök, Fenrir breaks free and devours Odin.

Wednesday takes its name from Odin, who was known to the Anglo-Saxons as Wōden (or Wodan). When Germanic peoples adopted the Roman system, Odin was paired with Mercury because they were both the gods of wisdom, says Larrington. As the leader of the Norse gods, Odin “incites War, but doesn’t fight himself," she explains.

In Norse mythology, Odin traveled around the Nine Realms—the interconnected worlds that make up the Norse cosmos—trying to prevent and prepare for Ragnarök. During this quest, he sacrificed one of his eyes to gain wisdom and hung himself from the world tree for nine days to master magic.

When he realized that Ragnarök was inevitable, he amassed an army to fight on his side. After Odin is eaten by Fenrir, his son Vidar avenges his father's death by killing the beast.

Over centuries of linguistic change, Wōdnesdæg (Old English for "Wōden's Day") eventually became "Wednesday."

Known as "Thunor's Day" or "Day of Thunder" to the Anglo-Saxons, Thursday is named after the Norse god Thor, the god of thunder, storms and strength. Because Thor shared many characteristics with Jupiter, the Romans' "Day of Jupiter" became "Thor's Day."

Despite his strength, command of the weather and possession of his hammer Mjölnir, Thor is actually made to look like a bit of a fool in Norse mythology, says Larrington.

After Mjölnir is stolen by a giant, Thor dresses up as a bride to get it back. “When the giants bring in the hammer to consecrate the marriage, they place it in the bride's lap, which may or may not be a ritual that actually took place,” she explains.

The celebration was short-lived. As soon as Thor had Mjölnir back in his hands, he used the hammer to kill the giants.

Friday derives from the Old English Frīgedæg, meaning "Frigg's Day." The day was the Germanic equivalent of the Romans' "Day of Venus." Both Venus and the Norse goddess Freyja represented love, beauty, fertility and marriage. Historians debate whether Frigg's Day originally referred to Frigg, Odin's wife, or Freyja. The two share overlapping traits and may have become conflated over time.

Larrington says one of the most famous stories in Norse mythology follows Frigg's efforts to stop the death of her son Baldur, who she had with Odin. After a prophecy foretold Baldur’s death, Frigg travels the realms and extracted promises from every living creature to not to harm him. Only mistletoe was overlooked, as it seemed too small and harmless to pose a threat.

Loki, the god of mischief, exploits the oversight by fashioning a weapon from mistletoe and orchestrating Baldur's death. Devastated, Frigg begs Hel, ruler of the underworld, to return Baldur to the living. Hel agrees, but only if every creature in existence mourns his death. The entire cosmos weeps—except for Loki in disguise—leaving Baldur trapped in the realm of the dead.

“[She] has this role as a loving, slightly desperate mother, who takes every precaution to try and protect her child,” says Larrington. “In the end, though, Baldur’s death is the start of the chain of events that leads to Ragnarök and the end of everything.”