Theodosius II (Greek: Θεοδόσιος), lay surname Christianopoulos (Χριστιανόπουλος), served as the Ecumenical Patriarch of Constantinople between 1769 and 1773.
He was elected Patriarch on 11 April 1769, at a time when Christians were persecuted after the withdrawal of the Russian forces following the Orlov Revolt.
Many Christians had helped the Russians, following the exhortations of the former Patriarch Seraphim II of Constantinople and other clerics.
Theodosius II made efforts to save the monasteries of Mount Athos from demolition, he freed prisoners, he supported schools and monasteries and, with cooperation with the Patriarch of Jerusalem Sophronius V of Jerusalem, he managed to keep the Holy Land under the jurisdiction of the Eastern Orthodox Church.
Theodosius II was forced to resign on 16 November 1773, following the machinations of the Metropolitan of Prousa, Meletius.