Senior Yazidi leaders have met with the Church of England in a bid to have their religion formally recognised.
ITV News international affairs editor Rageh Omaar reports:
Despite dating back thousands of years, the Yazidi tradition - considered a distant cousin of Christianity - is not classed as a world religion because none of it has been written down.
This means that despite persecution and genocide at the hands of so-called Islamic State militants two years ago, they cannot be considered a "persecuted religious group".
The assault came when the extremist fighters drove the Yazidis from their homes in in the town of Sinjar, declaring the minority group to be "devil-worshippers".
They were forced to flee to the nearby Mount Sinjar in the heat of an Iraqi summer in 2014, facing a stark choice between slaughter at the hands of the extremist fighters or death by dehydration on the mountain.
Air strikes by coalition forces helped beat back the onslaught, and drops of food and water were made.
Now, the Church of England - with the support of the AMAR Foundation - has struck a deal to help the Yazidis put their beliefs down on paper for the first time.
As part of their efforts to be recognised as an official religion, the Yazidis have also drawn up new rules in recent months which means that, instead of ostracising the women and girls raped by Islamic State fighters - as often happens in the Middle East, regardless of faith - they will be accepted back by their families and husbands.
"We issued a law that any girl who was freed and returned to us should be accepted back into Yazidi society," head of the Sinjar Yazidis, Mirza Haji Mirzi, said.
"What happened to them was forced on them, and they should not be shunned."
The Yazidis are monotheists, meaning they believe in one single God, who is the creator of the world.
They believe God put the world into the care of seven angels, with Melek Taus - or the Peacock Angel - as leader, causing both good and bad in the lives of humans.
Some followers of other monotheistic religions in the region have equated Melek Taus - who, according to religious lore, fell out of favour with God for a while before being redeemed - with their own fallen angel, Satan.
This link has formed the basis of much of the persecution of the Yazidis.