Oslo is the capital and most populous city of Norway. It constitutes both a county and a municipality. Founded in the year 1040 as 'Ánslo', and established as a kaupstad or trading place in 1048 by Harald Hardrada, the city was elevated to a bishopric in 1070 and a capital under Haakon V of Norway around 1300.

Personal unions with Denmark from 1397 to 1523 and again from 1536 to 1814 reduced its influence. After being destroyed by a fire in 1624, during the reign of King Christian IV, a new city was built closer to Akershus Fortress and named Christiania in the king's honour.

It was established as a municipality on 1 January 1838. The city functioned as a co-official capital during the 1814 to 1905 Union between Sweden and Norway. In 1877, the city's name was respelled Kristiania in accordance with an official spelling reform, a change that was taken over by the municipal authorities only in 1897. In 1925 the city, after incorporating the village retaining its former name, was renamed Oslo.

Oslo is the economic and governmental centre of Norway. The city is also a hub of Norwegian trade, banking, industry and shipping. It is an important centre for maritime industries and maritime trade in Europe.

The city is home to many companies within the maritime sector, some of which are among the world's largest shipping companies, shipbrokers and maritime insurance brokers.

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