Read it on the Internet, so it "must" be true.

Valkyries' Day
by W.Holidays
January 31
Valkyries are from Norse mythology. They were maidens who served Odin, the ruler of the Gods. They directed battles, disseminated death lots to warriors, and brought the souls of slain heroes to Valhalla.
The leader of the Valkyries was known as Freya or Freyja. She was the goddess of love, fertility, and beauty. She was a blonde, blue-eyed beauty and she rode the skies on a chariot drawn by cats. In Germany, she is identified with Frigg, the wife of Odin. Friday is named for her.