The Ecumenical Patriarch is the Archbishop of Constantinople–New Rome and ranks as primus inter pares (first among equals) among the heads of the several autocephalous churches that make up the Eastern Orthodox Church, often being regarded as the spiritual leader of the 300 million Orthodox Christians worldwide.

The Ecumenical Patriarchate of Constantinople is one of the most enduring institutions in the world and has had a prominent part in world history. The ecumenical patriarchs in ancient times helped in the spread of Christianity and the resolution of various doctrinal disputes.

In the Middle Ages they played a major role in the affairs of the Eastern Orthodox Church, as well as in the politics of the Orthodox world, and in spreading Christianity among the Slavic people.

Currently, in addition to the expansion of the Christian faith and the Orthodox doctrine, the patriarchs are involved in ecumenism and interfaith dialogue, charitable work, and the defense of Orthodox Christian traditions.

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