The Karaite Jewish community of Jerusalem purchased the codex about a hundred years after it was made. When the Crusaders conquered Jerusalem in 1099, the synagogue was plundered and the codex was held for a high ransom, which was paid with money coming from Egypt, leading to the codex being transferred there. It was preserved at the Karaite, then at the Rabbanite synagogue in Old Cairo, where it was consulted by Maimonides, who described it as a text trusted by all Jewish scholars. It is rumoured that in 1375 one of Maimonides' descendants brought it to Aleppo, Syria, leading to its present name.