The origin of this Byzantine building, which lies on the southern slope of the seventh hill of Constantinople in the neighborhood named ta Dalmatou and overlooks the Sea of Marmara, is not certain.

The comparison of the brickwork with those of the Pammakaristos and Chora churches suggests that the building was erected between the end of the thirteenth and the beginning of the fourteenth century, in the Palaiologan era.

[1] The proposed identification with the Monastery of Iasités (Greek: Μονῆ τοῦ Ἰασίτου), which lay in the neighborhood, remains uncertain.

At the same time he let Court Architect Mimar Sinan (who also designed the Friday Mosque) enlarge the existing complex.

[6] In 1741 Ahmet Agha – another chief eunuch (Ibrahim Pasha in the charter of his waqf had designated the current chief white eunuch of the Imperial Harem as administrator (Turkish: Mütevelli) [7] of the endowment)[4] – sponsored the construction of a small fountain (Turkish: Sebil).

Two of them – painted in the south apse – one depicting respectively the Archangel Michael (on the Conch) and the St. Hypatius (on the side wall), were still visible in 1930, but now have disappeared.