Gregory V (Γρηγόριος Ε΄, born Georgios Angelopoulos) was Ecumenical Patriarch of Constantinople from 1797 to 1798, from 1806 to 1808 and from 1818 to 1821. He was responsible for much restoration work to the Patriarchal Cathedral of St George, which had been badly damaged by fire in 1738. At the onset of the Greek War of Independence, as Ethnarch of the Orthodox Millet Gregory V was blamed by Ottoman Sultan Mahmud II for his inability to suppress the Greek uprising, even though he had actually condemned the Greek revolutionary activities. He was taken out of the Patriarchal Cathedral on Easter Sunday, 1821, directly after celebrating the solemn Easter Liturgy, and hanged (in full Patriarchal vestments) for three days from the main gate of the Patriarchate compound by order of the Sultan; his body was then taken down and delivered to a squad of Jews who were forced to drag it through the streets and finally threw it into the Bosphorus. . The body was later recovered by Greek sailors and was eventually enshrined in the Metropolitan Cathedral of Athens.He is commemorated by the Orthodox Church as an Ethnomartyr (Greek: Εθνομάρτυρας).
In his memory, the Saint Peter Gate, once the main gate of the Patriarchate compound, was welded shut in 1821 and has remained shut ever since.
The brutal executing of Gregory V, especially on the day of Easter Sunday, shocked and infuriated the Greeks, and Orthodox Russia. It caused also protests in the rest of Europe and reinforced the movement of Philhellenism. There are references that during the Greek War of Independence, many revolutionaries engraved on their swords the name of Gregory seeking revenge.