Last Roman Emperor, also known as Last World Emperor or Emperor of the Last Days, is a figure of medieval European legend, which developed as an aspect of Christian eschatology. The legend predicts that in the end times, a last emperor would appear on earth to reestablish the Roman Empire and assume his function as biblical katechon who stalls the coming of the Antichrist. The legend first appears in the 7th-century apocalyptic text known as the Apocalypse of Pseudo-Methodius; that and the oracles of the Tiburtine Sibyl are its two most important sources. It developed over the centuries, becoming particularly prominent in the 15th century. The notion of Great Catholic Monarch is related to it.