In Old Norse, it meant "chieftain", specifically one appointed to rule a territory in a king's stead.
[citation needed] For example, during the Viking age, the rulers of several of the petty kingdoms of Norway held the title of jarl, often wielding no less power than their neighboring kings.
The term jarl (Old Norse: jarl, Old Swedish: iarl, iærl, Old Danish: jærl) has been connected to various similar words across Germanic languages, such as Proto-Norse eril, Old English eorl (meaning warrior, hero, or chieftain, related to modern English earl), Old Saxon erl (man, nobleman), and Old High German erl- in personal names such as Erlaberaht.
[2][3] The word jarl is known in Norway from the scaldic poem Háleygjatal, dating from the late 9th century.
[5] In Eddic poetry, a jarl is often a free man of good standing, but not necessarily of high office.
According to the myth, the god Ríg fathers three sons—Thrall, Karl, and Jarl—who become the ancestors of the social classes: thralls, peasants, and the warrior nobility.
Based on Rígsþula, German historian Konrad Maurer traced the concept of jarl back to the legendary Norwegian king Harald Fairhair (c. 850 – c. 932).
[5] According to the Saga of Harald Fairhair, King Harald set a jarl in each county to collect taxes:[2][6] King Haraldr made this law everywhere he established his dominion over, that he took possession of all inherited property and made all farmers pay him land dues, both rich and poor.
[7] After the death of Birger Jarl, the title was replaced by that of a duke (Swedish: hertig) in the 13th century.
He divided the kingdom into four semi-independent earldoms, Northumbria went to the Norwegian, Erik of Lade, Thorkell the Tall was given East Anglia, and Eadric Streona had his preexisting appointment to Mercia confirmed.