was it joined with any other countries historically?
Yes, with Denmark and Sweden.
Norway
After Sweden broke out of the Kalmar Union in 1521, Norway tried to follow suit, but the subsequent rebellion was defeated, and Norway remained in a union with Denmark until 1814, a total of 434 years. 
where is the berg metro station located? It is located between Ullevål stadion and Tåsen stations which country are these places found in? Kingdom of Norway when was this station built? 10 October 1934 where does the afore-mentioned country get its name from? The English name comes from the Old English word "Norþweg".
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Norway [SEP] Union with Denmark
After Sweden broke out of the Kalmar Union in 1521, Norway tried to follow suit, but the subsequent rebellion was defeated, and Norway remained in a union with Denmark until 1814, a total of 434 years. During the national romanticism of the 19th century, this period was by some referred to as the "400-Year Night", since all of the kingdom's royal, intellectual, and administrative power was centred in Copenhagen in Denmark. In fact, it was a period of great prosperity and progress for Norway, especially in terms of shipping and foreign trade, and it also secured the country's revival from the demographic catastrophe it suffered in the Black Death.