These large settlements, one from the 6th-century Germanic Iron Age, the other from the Viking Age in the 9th to 11th centuries, evolved at the narrowest point on Limfjord as a result of the traffic between Himmerland to the south and Vendsyssel to the north.
In 1530 a large part of the town was destroyed by fire, and in December 1534 it was stormed and plundered by the king's troops after a peasants' revolt known as the Count's Feud led by Skipper Clement. From the 1550s to the 1640s, as a result of increased foreign trade, Aalborg enjoyed great prosperity, second only to that of Copenhagen.The population grew in parallel with the development of many fine buildings in the city as merchants benefitted from their shipping routes from Norway to Portugal.The herring fishery linked Aalborg to the East coast of England, across the North Sea, both in commercial competition and cultural exchange.During the Middle Ages a number of important institutions were established in Aalborg, including Budolfi Cathedral in the late 14th century and the Hospital of the Holy Ghost, a monastery and nunnery founded in 1451 to help those in need.The Aalborg Carnival, held at the end of May, is one of the largest festivals in Scandinavia, attracting some 100,000 people annually.
The major university is the University of Aalborg, founded in 1974, which has more than 17,000 students.
The town prospered, becoming one of the largest communities in Denmark.
Its prosperity increased when the merchant- and trade association Guds Legems Laug was established in 1481, facilitating trade with the Hanseatic League, The king frequently visited the town, where he held court and stayed in the old Aalborghus.
After Denmark ceded Norway to Sweden in 1814, Aalborg lost its important role as the country's centre for Norwegian trade.
Its former prosperity also suffered as a result of difficulties with the herring industry as the fish disappeared after the sea breached the Agger Tange (which had linked Thy with the rest of Jutland at the western end of Limfjord) in the 1825 North Sea storm.
The University College of Northern Denmark is one of seven new regional organisations while the Royal School of Library and Information Science (RSLIS) provides higher education in library and information science.