Complex sentence: In the late Ottoman period Muslim Albanians in the region began to affiliate themselves with the Albanian national movement, in contrast to the local Orthodox Albanian speaking population who remained Greek-oriented and identified themselves as Greeks.
Split into simpler sentences: In the late Ottoman period, Muslim Albanians in the region began to affiliate themselves with the Albanian national movement. The local Orthodox Albanian speaking population did not share the national ideas of their Muslim Albanian speaking neighbours, instead they remained Greek-oriented and identified themselves as Greeks.