Eugenius II (Greek: Εὐγένιος; c. 1780 – 27 July 1822) was the Ecumenical Patriarch of Constantinople from 1821 until his death in 1822.^[1][2] Prior to his election as Patriarch, he was Archbishop of Anchialos in Bulgaria.

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Eugenius was among the Archbishops held as hostages by Mahmud II along with Patriarch Gregory V when the Greek War of Independence broke out in 1821. On 10 April 1821, Gregory V was deposed and hanged by the Turks in the central gate of the Ecumenical Patriarchate. Archbishop Eugenius, still a prisoner at the time, was elected as the new Patriarch under the name Eugenius II.