Linked from
The 8 pages that link to Inca Civil War, each with the reason it gives.
Inca EmpireRelated: The succession struggle weakened imperial unity before Spanish invasion.
Francisco PizarroRelated: The conflict had weakened the empire shortly before Pizarro’s arrival.
AtahualpaRelated: Atahualpa's victory left the empire divided shortly before Pizarro arrived.
Battle of CajamarcaRelated: The recent conflict weakened imperial unity when Pizarro arrived.