Complex sentence: These people were then again banished by the people of the Old World, particularly a wizard, Kaja-Rang who bound them behind a boundary that would force any that tried to leave to walk straight to the Pillars of Creation.
Split into simpler sentences: These people were then again banished by the people of the Old World. A wizard, Kaja-Rang, placed them behind a boundary that would force any that tried to leave to walk straight to the Pillars of Creation.