The Byzantines never called themselves "Byzantines". This term is derived from Byzantium, the Roman name for Byzantion, the original name of the city that is now Istanbul. It was first used in 1557, over 100 years after the fall of the "Byzantine" Empire, when German historian Hieronymus Wolf published Corpus Historiæ Byzantinæ. The "Byzantines" called themselves Romans, while they were called Greeks by Western Europeans.