Jarl is the Scandinavian language cognate of Earl.
See Ríg for the account in Norse mythology of the warrior Jarl or Ríg-Jarl presented as the ancestor of the class of warrior-nobles.
Some dozen runic inscriptions on rune stones and metal pieces exist containing the phrase ekerilaR. The first word ek means "I", whereas the meaning of the word erilaR is unclear. Some believe it shall be read out "I, the Herul", others say it mean "I, the rune-carver" but the most widespread interpretation in modern research is that it actually means "I, the Jarl".
See also: Birger Jarl