Complex sentence: In spite of the efforts of William III after the defeat of Napoleon the Ashkenazi Dutch concentrated in Amsterdam in appalling slum conditions resisted integration and prejudice against foreign immigrants although not amounting to religious persecution continued through the mid 19th Century.
Split into simpler sentences: In spite of the efforts of William III after the defeat of Napoleon, the Ashkenazi Dutch concentrated in Amsterdam in appalling slum conditions and resisted integration. Prejudice against them, although not amounting to religious persecution, continued through the mid 19th Century.