who hunted along the coast. It is thought that people came from Doggerland, the North Sea land area between Denmark and England, which disappeared when the ice retreated and sea levels rose. The people who lived there must now find a new land. Some retreated south again, while a few passed the Norwegian Trench (which was considerably smaller than now) in its hunt for deer and the new country. Viking Age The region includes most of the scope of the old Gulating, which was founded around the year 900. The Gulating Act divided the country into the Western counties, which consisted of the former småkongedømmene that existed in the area before the unification of the 800's and then was converted to jarle judge. These were Sunnmørafylke (Sunnmøre), Firda County (Fjordane), Sygna County (Sogn), Hordafylke (Hordaland), Rygjafylke (Rogaland) and Egdafylke (Agder). Harald Hairfair united Norway and parts of Sweden west of Lake Vänern and Götaälv in the 9th century from his Castle Avaldsnes on Karmöy at Haugesund. Norway was named from the Way North by seafaring. Before the millennium, iron was introduced and used in agriculture, and there was a shortage of land to cultivate. In the same period, the kings' power increased, and large tax claims caused many to seek freedom and fortune abroad. Many emigrated, and looting became an alternative source of income. Effective boats and weapons made the Vikings feared among contemporary Christian Europeans. But the images of Vikings as bloodthirsty plunderers are not always representative. The Vikings were involved in a wealthy merchant trade, not only in Europe but also including the Byzantine Empire and the Baghdad Caliphate. Historically Vikings are often introduced with the Viking attack on Lindisfarne in 793, when they really made their mark in European history. The era ends with the Battle of Stamford Bridge in 1066. Vikings' seaworthiness and wanderlust resulted in new areas being developed. Norwegian settlers moved into the North Sea westward to Iceland, the Faroe Islands, Greenland, Shetland, Orkney, Isle of Man and the Hebrides. Settlements were established in the southeast corner of Ireland including in Dublin, Waterford and Wexford. Norwegians settled along the northwest area of England, principally in the area of modern-day Cumbria. The Norwegian Vikings also discovered Vinland, present-day America, long before Christopher Columbus. Christianization Christianity (Catholicism) became the dominant religion in Norway in the 11th century, but the religion was probably known among Norwegians already