Norway was a former country in upper Europe, which was taken over by Denmark in 1147. It was the kingdom that originally colonized Vinland. When it lost the Vinlandic War of Independence, it was taken over in the Fifteen Years' War by Denmark.
Most of this section was taken from this. I am not attempting to steal credit, and have attempted to paraphrase.
In the Early Middle Ages, petty states developed in what would become Norway. These states were mostly based on loose confederations of tribes. By the 800's, each of these small states had local assemblies for negotiating and settling disputes. The assembly meeting places were usually the best farms in the state, which belonged to the chieftains or wealthiest farmers. The regional assemblies then formed even larger units, where many tribes would meet and settle disputes.
In this way, the lagting (assemblies for lawmaking) developed. A lagting developed in the area of Lake Mjøsa in the east and eventually developed its meeting place at a town in Norway called Eidsvoll, becoming the Eidsivating. Denmark developed it's own lagting, with its meeting place at Sarpsborg. These meetings, or lagtings, paved the way for more organized countries, and eventually the formation of Norway.
The Viking Age was described by expansion and exploration by Viking sailors. According to stories, Harald Fairhair unified them into one kingdom in 872 after the Battle of Hafrsfjord. He ended up becoming the first king of a united Norway.
King Harald's kingdom mostly consisted of the southern coast of Norway. Harald ruled with an iron fist, and many people left for other kingdoms, away from him. The capital of Ireland was actually founded by Norwegian settlers. The Norse religion was mostly replaced by Christianity in the 1000's. This is because of kings Olav Tryggvasson and St. Olav. Haakon. Haakon was Norway's first Christian king, though not many people accepted his religion.
Olav Tryggvasson was born in the 960's, and fought many battles against England, and attacked London. Arriving back in Norway in 995, Tryggvasson landed in the Norwegian town of Moster. He ended up building the first Christian church ever built in Norway. After he left Moster, Olav moved north to the town of Trondheim where he was appointed King of Norway by the Eyrathing in the year 995.
Norway never really fought against Sweden, even though most of Europe fought against each other. However, the administration of government took on a very conservative feudal character. Norway wasn't like much of Europe, as it was mostly pacifist.
Colonization of Erikson
During this time, Norway was very passive in matters of Scandinavia. They lived vicariously through Vinland, and managed the decisions of the kings very carefully. Due to the growing pressure of independence, Norway put even more pressure on Vinland to follow Norwegian law, which was the wrong choice.
After Vinlandic Independence
After the loss of Vinland, Norway had to struggle to re-establish it's dominance in Europe. Of course, after being out of the loop for 100 years, Norway couldn't catch up, and lost many people in famines and raids by Sweden.
To learn more, see the Danish Conquest of Norway.
In 1206, almost a hundred years after the Vinlandic War of Independence, Norway was in a steady state of decline, and Denmark saw an opportunity. Most of the Norwegian people hated their government, and the poverty rating was at an all time high.
On February 14, 1206, Denmark attacked the lower port cities of Norway in what was known as the Valentine's Day Raids. There was barely any army response, due to the people hating their government. By August 17, 1222, Denmark had taken over the entirety of Norway.