The Conservation History of Çengelköy Hadji Ömer Efendi Mosque Through Ottoman Archival Documents

The Ottoman Archive documents provide crucial data for understanding the subtle changes and transformations that existing structures have experienced. This research focuses on the historical development of the Hadji Ömer Efendi Mosque, one of the oldest religious buildings in Çengelköy, especially in the 19th century, using data from the State Archives (BOA) and contemporary records. After a fire in 1878, the mosque was left unused for 16 years until 1894. Related documents from this period include a detailed plan for reconstructing the mosque and illustrations to guide the rebuilding process. The involvement of the local community and the significant support from the Ottoman Empire for the restoration of this relatively small mosque in a Bosphorus village are particularly noteworthy. The findings of the study indicate that the involvement of the local community, following the 1894 reconstruction process of the mosque, reflects a diversity of actors and approaches in the restoration practices of historic structures during the Ottoman period. Furthermore, it appears that the 1984 reconstruction project was not implemented to a considerable extent, as significant discrepancies can be observed when compared with the building’s present condition. Another survey book within the scope of the study has yielded valuable data regarding the repair techniques and construction materials in 19th century.