The Patriarch of the Church of the East (Patriarch of Babylon or Patriarch of the East) is the  patriarch, or leader and head bishop (sometimes referred to as Catholicos or universal leader) of the Church of the East. The position dates to the early centuries of Christianity in Persia, and the church has been known by a variety of names, including Nestorian Church, the Persian Church, the Sassanid Church, or East Syrian. In the 16th and 17th century the Church experienced a series of splits, resulting in a series of competing patriarchs and lineages. Today, the three principal churches that emerged from these splits, the Assyrian Church of the East, ancient church of the east and the Chaldean Catholic Church, each have their own patriarch, the Patriarch of the Assyrian Church of the East and the Patriarch of Babylon of the Chaldeans, respectively.