They are named after what could be seen in the sky Monday is Moon day (Monday=Lundi / moon=lune) Tuesday is Mars day (Tuesday=Mardi) Wednesday is Mercury day (Mercredi) Thursday is Jupiter day (Jeudi) Friday is Venus day (Vendredi) Saturday is Saturn day Sunday is Sun day ... it is much more obvious when you use Latin (or even French) instead of English ...

For the Anglish words: Monday = Moon Day Tuesday = Tiw's Day. Tiw was a god of combat and heroism in Norse mythology. Wednesday = Odin's Day. Odin is the chief deity of Norse Mythology. Thursday = Thor's Day. Thor, of course, is god of thunder. Friday = Freya's Day. Yet another figure from Norse mythology, Freya was a goddess of fertility and love. Saturday = Saturn's Day. Saturn was a Roman god of agriculture, often linked to the Greek god Cronus. Sunday = Sun Day.

"Planet English German French Remarks Sun Sunday Sonntag Dimanche Day of the Sun. The only anomaly here is the French name for the day which derives from the New Testament reference of the day as "Lord's Day" Moon Monday Montag Lundi Day of the moon. The French name simply uses the latin root for moon, lunae. Mars Tuesday Dienstag Mardi Day of Mars, but because the Romans venerated Mars as the god of war, it is the day of the war god. Tuesday comes from the Norse war god, Tiu or Tyr. The German name means "assembly day." Mercury Wednesday Mittwoch Mercredi Day of Mercury. This one makes the least sense. The Anglo-Saxon's decided to venerate Odin or "Woden" on this day and the roles of Mercury and Odin in their pantheons are completely unrelated. Mittwoch was created to replace the pagan reference to Odin and means "middle of the week" Jupiter Thursday Donnerstag Jeudi Day of Jupiter or Jove, Roman god of thunder and rain. The English name comes from the Anglo-Saxon replacement of Jupiter with Thor, the Norse god of thunder. "Donnerstag" literally means "Thunder day." Venus Friday Freitag Vendredi Day of Venus, the Roman goddess of love. Frigga and Freya were variously goddeses of love in the Norse mythos and replaced Venus in the German, English names. Saturn Saturday Samstag Samedi Day of Saturn, ancient Roman god of agriculture. I am not sure why the French word is "Samedi;" it is not consistent with the Latin root, dies Saturni." Source: http://michael.casavant.us/Game/cd.htm#Days_of_the_week_What_to_call_them Further information: http://home.alphalink.com.au/~umbidas/time_days.htm http://www.mystical-www.co.uk/time/days.htm