When the works belonging to the Ottoman period are examined, one of the main reference sources is undoubtedly the Ottoman archives. Apart from that, foundation certificates and foundation records are the documents supporting the studies to be done in this field. In this sense, we believe that the name of Keyhüsrev Bey Mosque in Sağman, based on Ottoman archives and foundation records, is wrong to be named Salih Bey Mosque in publications until today and it would be correct to call the building Keyhüsrev Bey Mosque

In many documents that we found in the Ottoman archives, it is seen that the name of the mosque in Sağman was known Keyhüsrev Bey Mosque in the Ottoman period, and it was mentioned by the same name until 1912 from the documents that included other units of the Foundation and the assignments of the mosque. There is no information about when it was named as Salih Bey Mosque after this date. In the study with the title “History of Ottoman Architecture”, which was first published by Godfrey Goodwin in 1971, it is seen that the name of the building was mentioned as “Sağmanbahçe Mosque”. The author does not give any information about the origin of the name of the building. In his work titled “Diyarbakır, a Rival to Iznik: a Sixteenth Century Tile Industry in Eastern Anatolia”, which he prepared in 1977, Julian Raby, gave only brief information about the tiles with the same name. Apart from the studies done by these two researchers, in the few works done in Turkey, brief information about the building was given and its name was reported as Salih Bey Mosque. The most comprehensive research among these studies is the published by Ayşıl Tükel under the name of “Multifunctional Salih Bey Mosque in Sağman”. Tükel, mentions in her study that brief information about the early publications. It can be accepted that the building has reached the present day with the name of Salih Bey with the effect of all these works.

In the Ottoman archives, we did not encounter a mosque named Salih Bey in Sağman. But, during the same archive scans, it is possible to encounter many different documents related to the Keyhüsrev Bey Foundation Mosque. In a document dated 1560 in the Ottoman archives, it is stated that Keyhüsrev Bey requested permission from the central administration to build a mosque in Sağman and it was accepted. In addition, the same document states that an old mosque that already existed in the region was destroyed. When considered in this sense, it is clear that the construction of the mosque started in the time of Keyhüsrev Bey. Another point to be considered here is whether the mosque was completed following the original plan. The mosque has taken on a multi-functional plan, with spaces consisting of different units consisting of four rooms and an iwan on the east and west sides of the northern façade of the single-domed prayer area in the center. However, we believe that it would be correct to think that the single-domed section was started during the reign of Keyhüsrev Bey and completed in 1567 during his reign. We think that the places in the east and west and the tomb in the south were added to the plan later. One of the architectural proofs supporting this idea is that a part of the space in the west was built based on the minaret rostrum.

The tiles of the building, which have no trace today, have a very important and special place in Ottoman tile art. In 2001-2002, the majority of the remaining tiles were stolen from the building, but the tiles in the hands of the thieves caught by the security forces were handed over to the Elazig Museum. The couplets and ghazals located in the central hatayi motif among the tiles show a unique feature among the tiles of the Ottoman period. Among the tiles known to exist in the building, although they have not reached the present day, the two-line couplet and ghazals in the center of the hatayi motif show a unique feature among the tiles of the Ottoman period. One of these scripts, which was found in four Hatayi motifs side by side, could not be read, and some of the other three texts were read and written by Tükel, albeit incompletely. Tükel did not mention the meanings of these writings but stated that there were three Persian and one Arabic Sufi writings.

Accordingly, in the first expression, the couplet “Since in the end the crown and dais of kingship fall into ruin; Hold yourself to have become Sultan on the throne of the world “ is read in the divan of Suleiman the Magnificent, which he wrote with the pen name Muhibbi. On another tile that is only partially readable, it is written in Persian: “If I taste a little salt from the salt shaker of your lip…., …., I will be without salt and tasteless”. Unfortunately, despite all our research, we could not determine which poet this poem belongs to. In another tile, Arabic; The text “There is a healing for hearts in meeting/meeting with a loved one” is read. It is stated that this word is one of the different expressions transferred by changing the words from the sentence “Likâu’l-halîl şifau’l-alîl” (Your friend’s face is the cure for the patient) in the chapter about friendship in the book “Fîhi Ma Fîh” compiled from the conversations of Mevlâna Celaleddin Rumi. It is possible to see the same sentence in the Beyazıt II. Bridge in Geyve and the painting “Turtle Trainer” by Ottoman Hamdi Bey. These tiles, on which there are Turkish, Persian and Arabic inscriptions, show that the tile master has a command of these three languages enough to write. In addition, the fact that the writings in these three languages are parts of literary works reveals the intellectual side of the master and the patron.