At some of the mithraeums that have been found below churches, such as the Santa Prisca Mithraeum and the San Clemente Mithraeum, the ground plan of the church above was made in a way to symbolize Christianity's domination of Mithraism. The cult disappeared earlier than that of Isis. Isis was still remembered in the Middle Ages as a pagan deity, but Mithras was already forgotten in late antiquity. "John, the Lord Chamberlain", a 1999–2014 series of historical mystery novels, depicts a secret Mithraist community still active in Justinian's court (r. 527–567), but there is no historical evidence for such a late survival of the religion.