<Tr> <Td> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> </Td> </Tr> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> <P> The age of settlement of Iceland (Icelandic: landnámsöld) is generally believed to have begun in the second half of the 9th century, when Norse settlers migrated across the North Atlantic . The reasons for the migration may be traced to a shortage of arable land in Scandinavia and civil strife brought about by the ambitions of the Norwegian king Harald I of Norway . Unlike the British Isles, Iceland was unsettled land and could be claimed without conflict with existing inhabitants . </P> <P> On the basis of Íslendingabók by Ari Thorgilsson, and Landnámabók, the years 870 and 874 have traditionally been considered the first years of settlement . Historian Gunnar Karlsson notes that these sources are largely unreliable in terms of dating settlement . Traditionally, the Icelandic Age of Settlement is considered to have lasted from 874 to 930, at which point most of the island had been claimed and Alþingi (Althingi), the assembly of the Icelandic Commonwealth, was founded in Þingvellir (Thingvellir). Almost everything known about the first settlers comes from Íslendingabók, and Landnámabók, two historical records preserved in skin manuscripts . Estimates of the number of initial settlers range between 311 and 436 . </P>

When was iceland believed to be first inhabited