The Chaldean Church started using this name in 1445, when Pope Eugenio IV called the colony of Syro-Oriental of Cyprus, who had accepted communion with Rome, Chaldean. In 1553, Pope Julius III consecrated Abbot John Sulaqa and nominated him to be the first Patriarch of Babylon of the Chaldeans with the name of Simon VIII. At first, the Church grew steadily. Then, because of persecutions, genocides, deportations and discriminations, the number of faithful fell. Today membership is estimated to be of around 700.000, the majority of whom are in Iraq and Iran.

    The Patriarchal seat is in Baghdad. The liturgy is close to the Syrian tradition, but the communities are switching to Arabic as the liturgical language. The Catholic group is promoting the ecumenical encounter with the sister Orthodox Church.
    In 1908, the Exarchate of Palestine and Trans-Jordan was established in Jerusalem. The community in Jerusalem is reduced to a few families. The community in Jordan has grown considerably in the past years due to the arrival of many refugees from Iraq.