Church of Jerusalem
The Church of Jerusalem is the mother church of all of Christendom, because it was in Jerusalem that the Church was established on the day of Pentecost with the descent of the Holy Spirit on the disciples of Jesus Christ. From Jerusalem the gospel of Christ was spread to the world.
As Christianity spread, and the persecutions of the Jews by Roman authorities in their homeland increased, causing the dispersion of many of the Christians from Jerusalem, the import of this church and its impact on the ongoing life of the whole Church diminished. As other churches gained ascendency, namely the Churches of Rome, Constantinople, Alexandria, and Antioch, the Church of Jerusalem was accorded a place of honor with them among the five original Christian patriachates of the Christian world, called the Pentarchy.
The current Patriarch of Jerusalem is His Beatitude Patriarch Irenaios I.