In the early sixteenth century, a large migration of Albanians into Kosovo resulted in a sizeable ethnic Albanian presence in some parts of Western Kosovo which continued into the next century. Historian Noel Malcolm challenges this view, using Ottoman documents that recorded migrants coming into the Kosovo region from the 15th to the 18th century and Albanian Catholic sources from the 17th century of northern Albania which recorded migrations out of the region, Malcolm argues majority of the migrants into the Kosovo region during this period were not Albanian. The population of Kosovo was also much bigger than that of northern and central Albania and its rate of growth lower. Kosovo was part of the wider Ottoman region to be occupied by Austrian forces during the Great War of 1683–99, but the Ottomans re-established their rule of the region. Such acts of assistance by the Austrian Empire (then arch-rivals of the Ottoman Empire), or Russia, were always abortive or temporary at best. In 1690, the Serbian Patriarch Arsenije III led thousands people from Kosovo to the Christian north, in what came to be known as the Great Serb Migration. Anscombe casts doubt on the fact that this exodus affected Kosovo, since there is no evidence that parts of Kosovo were depopulated. Evidence of depopulation can only be found in areas between Niš and Belgrade. Some Albanians from Skopje and other regions were displaced in order to fill some areas around Niš, but there is no evidence that such events took place in Kosovo. In 1766, the Ottomans abolished the Patriarchate of Peja and fully imposed the "jizya" on its non-Muslim population.