In the 1300s, Moorish ruler, Yusuf I, Sultan of Granada, converted the old 9th century fortress into the royal palace. ← Previous Next → In the 1300s, Moorish ruler, Yusuf I, Sultan of Granada, converted the old 9th century fortress into the royal palace. In the 1300s, Moorish ruler, Yusuf I, Sultan of Granada, converted the old 9th century fortress into the royal palace.