Agder

Agder is a county (fylke) and traditional region in the southern part of Norway and is coextensive with the Southern Norway region. The county was established on 1 January 2020, when the old Vest-Agder and Aust-Agder counties were merged. Since the early 1900s, the term Sørlandet ("south country, south land, southland") has been commonly used for this region, sometimes with the inclusion of neighbouring Rogaland. Before that time, the area was considered a part of Western Norway.
The area was a medieval petty kingdom, and after Norway's unification became known as Egdafylki and later Agdesiden, a county within the kingdom of Norway. The name Agder was not used after 1662, when the area was split into smaller governmental units called Nedenæs, Råbyggelaget, Lister, and Mandal. The name was resurrected in 1919 when two counties of Norway that roughly corresponded to the old Agdesiden county were renamed Aust-Agder (East Agder) and Vest-Agder (West Agder). Even before the two counties joined in 2020, they cooperated in many ways; the University of Agder had sites in both Aust-Agder and Vest-Agder, as did many other institutions, such as the Diocese of Agder og Telemark, the Agder Court of Appeal, and the Agder Police District.
The origin of the name Agder is uncertain. The Old Norse form of the name is Agðir or Egðafylki, and may derive from Old Norse ǫgð or Indo-European root *ak-, 'to be sharp', suggesting 'the land that juts out (into the sea)'. This same root may also appear in place names like Agdenes, Aga (in Bømlo) and Agdestein (in Stord). Another interpretation links it to Old Norse agi, meaning 'rough seas', which would make Agder 'the land by the turbulent sea'.
The Old Norse term for the inhabitants of the area was Egðir. The Egðir are believed to be the same etymologically as the Augandzi people mentioned in the Getica of Jordanes, who wrote of Scandza (Scandinavia) in the 6th century. If Jordanes's Scandza is a palatalized form of *Scandia, then Augandzi is likely a palatalized form of *Augandii, residents of *Augandia.
On 1 January 1838, the formannskapsdistrikt law went into effect, creating local municipalities all over Norway. The municipalities have changed over time through mergers and divisions as well as numerous boundary adjustments. When Agder county was established on 1 January 2020, it had 25 municipalities.
Norway of the Viking Age was divided into petty kingdoms ruled by chiefs who contended for land, maritime supremacy, or political ascendance and sought alliances or control through marriage with other royal families, either voluntary or forced. These circumstances produced the generally turbulent and heroic lives recorded in the Heimskringla.
For example, the Ynglinga saga tells us that Harald Redbeard, chief of Agðir, refused his daughter Åsa to Gudröd Halvdanson, on which event Gudröd invaded Agðir, killed Harald and his son Gyrd, and took Åsa whether she would or no. She bore a son, Halvdan (the Black), and later arranged to have Gudröd assassinated. Among the royal families, these events seem to have been rather ordinary. Her word was the last in the argument, as her grandson, Harald Fairhair, unified Norway.
Prior to the Viking Age is a gap in the region's history for a few hundred years, but in Jordanes we also find regions of the same but earlier forms of names, presumably also petty kingdoms under now unknown chiefs. The previous most credible source, Ptolemy, gives the briefest of sketches, only citing all of Norway as the Chaedini ("country people"). Perhaps the difference between kingdoms was not sufficiently important to cite them individually.
Prior to then the most credible and respected source, Tacitus in Germania Chapter 44 described the Suiones, who were divided into civitates (kingdoms?) along the coast of Scandinavia and were unusual in owning fleets of a special type of ship. These were pointed on both ends and were driven by banks of oars that could be rearranged or shipped for river passage. They did not depend on sail (so Tacitus says) but other than that they do not differ from Viking ships. These civitates went all the way around Scandinavia to the Arctic, or at least to regions of very long days, where they stopped.
It seems clear that in the Roman Iron Age Norway was populated by people of the same identity as Sweden, who were called the Suiones by Latin sources. In settling the coast at some point in prehistory they had been divided into civitates by the terrain. These states took on mainly geographical names or names of individuals or mythological characters. Agder was one of them.
After the unification of Norway by Harold Fairhair and army and allies in the 10th century, all the civitates became provinces (fylker) and after their conversion to Christianity, they became dioceses or parishes. The development of Old Norse into local dialects and the dissimilation of customs due to isolation added an ethnic flavor to the area, which is cherished today.