Complex sentence: Bishop Chrysostomos of Zakynthos (1890-1958) was the Metropolitan Bishop of Zakynthos during the Second World War, and a key figure in saving the entire, 275-person strong Jewish population of the island.
Split into simpler sentences: Bishop Chrysostomos of Zakynthos (1890-1958) was the Metropolitan Bishop of Zakynthos during the Second World War. His Eminence was key to saving the entire, 275-person strong Jewish population of the island.