It was the Russo-Turkish War of 1768-1774 that led to an untimely death: accused of collusion with the Russian Empire, he was deposed in June 1769 and sent to Istanbul where he was tried and sentenced to death for treason with the Grand Dragoman Nicolas Soutzo and the Grand Vizier Yağlıkçızade Mehmed Emin Pasha. In September 1769, Callimachi is tied up and his decapitated head is exposed to the Bâb-ı Hümâyûn, that is to say to the outer door of the Topkapı Palace, with a yafta (explanatory notice) specifying his crimes.
