Complex sentence: Gregory had high hopes of reconciling Europe, unifying the Greek and Latin churches, and launching a new crusade: to that end, he announced the Council of Lyon, to be held in 1274, and worked to arrange the election of an Emperor.
Split into simpler sentences: Gregory had high hopes of reconciling Europe, unifying the Greek and Latin churches, and launching a new crusade. To that end, he announced the Council of Lyon, to be held in 1274, and worked to arrange the election of an emperor.