Who ruled Oslo?

Oslo sits at the head of the Oslofjord, a long inlet reaching about 100 kilometres north from the Skagerrak into the farmland of eastern Norway. The sheltered water and the fertile country around it made the site a natural market and royal seat. For much of its history, though, Oslo was a provincial town in a kingdom ruled from abroad, and it only became a true national capital, and a large city, after 1814. Fires, plague and foreign kings shaped it as much as the fjord did.

Farmers and seafarers lived around the inner fjord throughout the Viking Age, when the region, known as Viken, was often claimed by Danish kings. According to the sagas, King Harald Hardrada founded a trading town here around 1049, but excavations have found Christian graves from before 1000, suggesting an older settlement. The town grew up east of the Aker river, around churches, a royal residence and the bishop's seat established around 1070. Saint Hallvard, a local martyr, became its patron saint.

Oslo reached its medieval peak under Haakon V, who reigned from 1299 to 1319, lived in the town and began building Akershus Fortress on a headland above the harbour. Historians date Oslo's status as Norway's capital from his reign. The Black Death reached Norway in 1349 and killed a large part of the population, and in the following century German merchants of the Hanseatic League dominated the town's foreign trade. When the crowns of Norway and Denmark were joined from 1380, and then bound into the Kalmar Union with Sweden from 1397, the kings lived in Copenhagen, and Oslo shrank to a regional administrative centre.

Under Denmark-Norway, Oslo, like most Nordic towns, was built of wood and burned repeatedly. After a three-day fire in 1624, King Christian IV ordered that the old town be abandoned and a new one laid out on a regular grid beneath the walls of Akershus, across the bay. He named it Christiania after himself. Growth was slow at first, but in the eighteenth century timber exports, shipbuilding and trade made the town prosperous, and the university was founded in 1811.

The great turning point came in 1814. Denmark, defeated in the Napoleonic Wars, ceded Norway to Sweden; the Norwegians adopted their own constitution and, after a brief war, accepted a union under the Swedish king while keeping their own parliament and government. Christiania became the capital of the kingdom within Sweden–Norway, and acquired a royal palace, a parliament building (the Storting, opened in 1866) and a national theatre. Industry along the Akerselva river and migration from the countryside lifted the population from about 10,000 in 1814 to about 230,000 by 1900; by 1850 it had overtaken Bergen as the largest city in the country. The spelling changed to Kristiania in 1877.

When the union with Sweden was dissolved in 1905, the city became the capital of a fully independent Norway. In 1925 it took back its medieval name, Oslo, since a capital named after a Danish king seemed out of place. On 9 April 1940 Nazi Germany invaded; the sinking of the cruiser Blücher in the Oslofjord delayed the attack long enough for King Haakon VII and the government to escape, but the city remained occupied until May 1945. The merger with the surrounding municipality of Aker in 1948 created the large modern city. On 22 July 2011 a far-right terrorist set off a bomb in the government quarter, killing eight people, before murdering 69 more on the island of Utøya. Oslo today has about 700,000 inhabitants and is Norway's political, financial and shipping centre.