In the lead up to Istanbul's year as European Capital of Culture in 2010, a number of preservation initiatives were set in motion to recover the city's cosmopolitan Ottoman past. Its non-Muslim heritage was remapped through public events and restoration projects. This article focuses on the discourses and practices that surrounded a single building: Haskoy Mayor Synagogue. It traces how this forgotten historical synagogue was rediscovered and turned into a site of memory and negotiation. The building had lost its original function, decayed, and been appropriated for other uses, including metal and rubber manufacturing. The European Capital of Culture program provided funds for the building's restoration at the request of the local Jewish community. But what brought it into great public attention was the installation of a piece of artwork by a Romanian-American artist, Serge Spitzer. With this attention, Mayor Synagogue was the subject of public debates that negotiated its past and future, and called into question the idea of associating the building only with its Jewish history at the expense of its contemporary use in a gentrifying neighborhood. But there was an unnoticed wider reality: the attempts to rebrand Istanbul by recovering its old multiculturalism was also a way to avoid acknowledging the city's new multicultural population.