According to the sagas, the Northern Isles were Christianised by Olav Tryggvasson in 995 when he stopped at South Walls on his way from Ireland to Norway. The King summoned the jarl Sigurd the Stout and said "I order you and all your subjects to be baptised. If you refuse, I'll have you killed on the spot and I swear I will ravage every island with fire and steel." Unsurprisingly, Sigurd agreed and the islands became Christian at a stroke, receiving their own bishop, Henry of Lund (also known as "the Fat"), who was appointed sometime prior to 1035. The greatest source of Scottish influence after the appointment of the Scottish earls in the 13th century was probably through the church, although it is clear that Scots influence on the culture of Orkney and Shetland was fairly limited until the close of the 14th century or later. An influx of Scottish entrepreneurs helped to create a diverse and independent community that included farmers, fishermen and merchants that called themselves Communitas Orchadensis and who proved themselves increasingly able to defend their rights against their feudal overlords, be they Norwegian or Scots. This independence of mind may have been fostered by the influence of Norwegian government which was essentially communal and federal by contrast with Scotland. It was not until the mid-16th century that the Norse institutions were replaced by Scottish systems following large-scale immigration from the south and the islanders were probably bi-lingual until the 17th century. Once again, the situation in the Hebrides is much less clear. There was a Bishop of Iona until the late 10th century and there is then a gap of more than a century, possibly filled by the Bishops of Orkney, before the appointment of the first Bishop of Mann in 1079. The conversion of Scandinavian Scotland and the resultant end to slavery and integration of Viking society into mainstream European culture was a significant event. It took place at an early date, although the popular image of marauding berserkers and of the Norse as "enemies of social progress" remains despite considerable evidence that in their latter phase the Norse-speaking populations were rather "enlightened practitioners of maritime commercial principles". Þings were open-air governmental assemblies that met in the presence of the jarl and the meetings were open to virtually all free men. At these sessions decisions were made, laws passed and complaints adjudicated. Examples include