After the recapture of Constantinople (1261) artistic production in Byzantium experienced a recovery. In the capital of Byzantium itself this period is marked by the mosaic panel of the Deesis in the Hagia Sophia. This work constitutes a ‘one-off’ in Byzantine art. This fact poses a series of questions concerning the dating, the creator and the patron of the mosaic, as well as the reasons for its creation, given that no source makes any reference to these matters. The present study attempts to re-examine these issues.