The name Oslo is derived from the words Ás, the Old Norse name for the Norse Godhead, and lo, meaning ‘pasture’, yielding roughly ‘the fields of the gods’.
The city was originally founded in 1049 by King Harald Hardråda (Harald Hard-Ruler), whose son Olav Kyrre (Olav the Peaceful) set up a cathedral and a corresponding bishopric here. In the late 13th century, King Håkon V created a military presence by building the Akershus Festning (Akershus Fortress) in the hope of deterring the Swedish threat from the east. After the mid-14th-century bubonic plague wiped out half of the country’s population, Norway united with Denmark and, from 1397 to 1624, Norwegian politics and defence were handled from Copenhagen. Oslo slipped into obscurity and, in 1624, it burned to the ground. It was resurrected by King Christian IV, who rebuilt it on a more easily defended site and renamed it Christiania, after his humble self.
For three centuries, the city held on as a seat of defence. In 1814 the framers of Norway’s first constitution designated it the official capital of the new realm, but their efforts were effectively nullified by Sweden, which had other ideas about Norway’s future and unified the two countries under Swedish rule. In 1905, when that union was dissolved and Norway became a separate kingdom, the stage was set for Christiania to flourish as the capital of modern Norway. It reverted to its original name, Oslo, in 1925 and the city has never looked back.