History of Oslo's name
Erroneously, it was once assumed that Oslo meant "the mouth of the Lo river", referring to a lost name of the river Alna. This apocryphal story is not only ungrammatical (the correct form would be Loaros, cf. Nidaros), but the name Lo is not recorded anywhere before Peder Claussøn Friis first used it in the same work in which he proposed this etymology. The name Lo is now believed to be a back-formation arrived at by Friis in support of his spurious etymology for Oslo.
During the Middle Ages the name was initially spelt "Áslo" and later "Óslo". The earlier spelling suggests that the first component ás refers to the Ekeberg ridge southeast of the town. The word ás (in modern Norwegian ås) with the meaning 'ridge' is a common component in Norwegian place names (se for instance Ås and Åsnes). The most likely interpretation would therefore be "the meadow beneath the ridge".
An alternative interpretation could be "the meadow of the gods" (the word ás then refers to the Aesir). But the word ás with the meaning 'god' is not known from any other Norwegian place names, and is therefore less plausible.
A fire in 1624 destroyed much of the medieval city, and when the city was rebuilt it was moved westwards in to be closer to the Akershus Fortress. King Christian IV of Denmark and Norway named the reborn city Christiania. The old site east of Aker river was not abandoned however and the village of Oslo remained as suburb outside the city gates. According to an official spelling reform (that changed ch to k) the form was changed to Kristiania in 1877. (The same year the city names Christiansand and Christiansund were changed to Kristiansand and Kristiansund - and the name of the county Christians Amt was changed to Kristians Amt.) The new form was used in all official documents and publications of the Norwegian State, but not by the municipality itself. The city continued to use the old form until 1897, then they also changed to Kristiania (without any formal or official decision).
Restoration of the Oslo name
After the 1624 establishment of Christiania near Akershus fortress, the original site of the town was rebuilt and served as suburb outside the city gates. This village east of the river had preserved the name "Oslo". After the 1859 and 1878 expansion of city borders to include the surrounding Aker municipality, the village of Oslo was included in Christiania municipality. The entire city was renamed "Oslo" by a law of 11 July 1924, effective 1 January 1925—a decision that caused much debate.
When the city in general now took up the name of Oslo, the eastern district of the city that had preserved the name became known simply as Gamlebyen (Old Town). The old square of Christian IV's city was named Christiania torv in 1958, and this name (with the old ch-form) is still in use on signs and maps. Christian IV's city with straight streets and right angels is now known as Kvadraturen ("the Square") and covers large parts of modern Oslo's centre, in 2009 it was proposed to rename this area Christiania.
The city was referred to as Tigerstaden (the City of Tigers) by the author Bjørnstjerne Bjørnson around 1870, due to his perception of the city as a cold and dangerous place. This name has over the years achieved an almost official status, to the extent that the 1000-year anniversary was celebrated by a row of tiger sculptures around city hall. The prevalence of homeless and other beggars in more recent times led to the slight rewording of the nickname into Tiggerstaden (the City of Beggars).
- Jørgensen, Jon G. "Peder Claussøn Friis". In Helle, Knut. Store Norske Leksikon (in Norwegian). Oslo: Kunnskapsforlaget.
- Alna – elv i Oslo, Store Norske Leksikon (in Norwegian)
- http://snl.no/Oslo/historie read online May 31, 2013.
- Oslo byleksikon. Edited by Reidar Hanssen. Oslo: Kunnskapsforlaget, 1987.
- http://www.osloby.no/nyheter/Oslo-sentrum-blir-Kristiania-6609482.html read online May 31, 2013.