A legend was attached to Gog and Magog by the time of the Roman period, that the Gates of Alexander were erected by Alexander the Great to repel the tribe. Romanized Jewish historian Josephus knew them as the nation descended from Magog the Japhetite, as in Genesis, and explained them to be the Scythians. In the hands of Early Christian writers they became apocalyptic hordes, and throughout the Medieval period variously identified as the Vikings, Huns, Khazars, Mongols, Turanians or other nomads, or even the Ten Lost Tribes of Israel.