Oslo was founded as a city at the end of the Viking Age in 1040 under the name Ánslo, and established as a kaupstad or trading place in 1048 by Harald Hardrada.

[20] Oslo's population was increasing at record rates during the early 2000s, making it the fastest growing major city in Europe at the time.

To the north and east, wide forested hills (Marka) rise above the city giving the location the shape of a giant amphitheatre.

Not only has no evidence been found of a river "Lo" predating the work where Peder Claussøn Friis first proposed this etymology, but the very name is ungrammatical in Norwegian: the correct form would have been Loaros (cf.

[37] The seal of Oslo shows the city's patron saint, St. Hallvard, with his attributes, the millstone and arrows, with a naked woman at his feet.

[40] Recent archaeological research, however, uncovered Christian burials which could be dated to prior to AD 1000, evidence of a preceding urban settlement.

The churches and abbeys became major owners of large tracts of land, which proved important for the city's economic development, especially before the Black Death.

In 1380, Norway was the weaker part in a personal union with Denmark, and Oslo's role was reduced to that of provincial administrative centre, with the monarchs residing in Copenhagen.

At that time the area called Oslo (now Gamlebyen or Old Town) was a village or suburb outside the city borders east of Aker river.

Efforts to stop the invasion, most notably the sinking of the Blücher, delayed the occupation of Oslo for several hours which allowed King Haakon to escape the city.

[77] He added a classical portico to the front of an older structure, and a semicircular auditorium that was sequestered by Parliament in 1814 as a temporary place to assemble, now preserved at Norsk Folkemuseum as a national monument.

Linstow also planned Karl Johans gate, the avenue connecting the Palace and the city, with a monumental square halfway to be surrounded by buildings for University, the Parliament (Storting) and other institutions.

In Oslo, the German architect Alexis de Chateauneuf designed Trefoldighetskirken, the first neo-gothic church, completed by von Hanno in 1858.

A number of landmark buildings, particularly in Oslo, were built in the Functionalist style (better known in the US and Britain as Modernist), the first being Skansen restaurant [no] (1925–1927) by Lars Backer, demolished in 1970.

Kunstnernes Hus art gallery by Gudolf Blakstad and Herman Munthe-Kaas (1930) still shows the influence of the preceding classicist trend of the 1920s.

Most government offices, including that of the Prime Minister, are gathered at Regjeringskvartalet, a cluster of buildings close to the national Parliament, the Storting.

Therefore, one of the mayor's most important roles is that of the ceremonial head of the city and its public face, similar to that of the President of the Storting at the national level.

[85] As of 2006[update], it is ranked tenth according to the Worldwide Cost of Living Survey provided by Mercer Human Resource Consulting[86] and first according to the Economist Intelligence Unit (EIU).

[92] The climate action plan for the Port of Oslo includes implementing a low-carbon contracting process, and installing shore power for vessels which are docked.

The government has recently invested large amounts of money in cultural installations, facilities, buildings and festivals in the City of Oslo.

Grønland, the central areas around Youngstorget and Torggata, Karl Johans gate (the main pedestrian thoroughfare), Aker Brygge and Tjuvholmen, Sørenga, and the boroughs of Frogner, Majorstuen, St. Hanshaugen / Bislett, and Grünerløkka all have a high concentration of cafes and restaurants.

The World Cup Biathlon in Holmenkollen is held every year and here male and female competitors compete against each other in Sprint, Pursuit and Mass Start disciplines.

[128] Other examples of annual events in Oslo are Desucon, a convention focusing on Japanese culture[129] and Færderseilasen, the world's largest overnight regatta with more than 1100 boats taking part every year.

For instance, Nobel Prize-winning author Sigrid Undset grew up in Oslo, and described her life there in the autobiographical novel Elleve år (1934; translated as The Longest Years; New York 1971).

[134] In recent years, novelists like Lars Saabye Christensen, Tove Nilsen, Suresh Chandra Shukla, Jo Nesbø and Roy Jacobsen have described the city and its people in their novels.

The newspapers Aftenposten, Dagbladet, Verdens Gang, Dagens Næringsliv, Finansavisen, Dagsavisen, Morgenbladet, Vårt Land, Nationen and Klassekampen are published in Oslo.

Due to the cold climate and proximity to major forests bordering the city, skiing is a popular recreational activity in Oslo.

[151] Oslo is also covered by a bus network consisting of 52 city lines, as well as regional buses to the neighboring county of Akershus.

The suburbs with the highest proportions of people of immigrant origin were Søndre Nordstrand, Stovner and Alna, where they formed around 50 percent of the population.

Other large immigrant groups are people from Sri Lanka, Vietnam, Turkey, Morocco, Iraq & Kurdistan region and Iran & Kordestan province.