Bishops from the Iraq-based Chaldean Catholic Church met in Rome for security reasons on Monday for a synod to elect a new patriarch to lead what is one of the world's oldest Christian churches.
The synod of around 15 bishops is being held after former patriarch Emmanuel III Delly resigned after reaching the age limit for his post of 85 years.
It was being held as a security precaution in Rome instead of Baghdad where the patriarchate is based.
The church recognises the authority of the pope and the Vatican but retains its own hierarchy.
Its official language is Aramaic -- the language that would have been spoken by Jesus Christ -- and it traces its origins back to the Apostle Thomas.
Bishops came from Baghdad, Kirkuk and Mosul but also from Europe and North America where hundreds of thousands of Iraqi Christian exiles have moved in the decade since the 2003 US-led invasion.
The duration of the synod is not predetermined.
Among those in attendance was Monsignor Antoine Audo, bishop of the war-torn Syrian city of Aleppo and head of the Catholic charity Caritas-Syria.
Christians were singled out for discrimination following the US-led invasion and were identified as supposed allies of Western "crusaders". Clergymen were killed and abudcted while several churches were bombed.
The Chaldean Church had 550,000 followers in Iraq before 2003 and 150,000 in the diaspora. It now has around 150,000 followers in Iraq and 550,000 abroad.
It faces the challenge of engaging with Iraqi society despite ongoing violence and Islamist threats and the burning question of whether to stay in the country or join the massive recent exodus.
"We need a leader who can help us see the future and who can bring people together," Louis Sako, the bishop of Kirkuk, told Vatican Radio.
The Chaldean Church recognised Rome's authority in 1551 but a union only became definitive in 1830.
The synod is being presided by Argentinian cardinal Leonardo Sandri, prefect of the Vatican's Congregation for the Eastern Churches.