Banaz Mahmod, 20, was strangled with a boot lace, stuffed into a suitcase and buried in a back garden.
Her death is the latest in an increasing trend of such killings in Britain, home to some 1.8 million Muslims. More than 100 homicides are under investigation for being potential "honour killings".
Mahmod Mahmod, 52, and his brother Ari Mahmod, 51, planned the killing during a family meeting, prosecutors told the court.
Two others have pleaded guilty in the case. Two more have fled the country. Sentencing is expected this month.
The men accused the young woman of shaming her family by ending an abusive arranged marriage, becoming too westernised and falling in love with a man who did not come from their Iraqi village. The Kurdish family came to Britain in 1998 when Banaz Mahmod was just 11.
"She was my present, my future, my hope," said Rahmat Suleimani, 29, Banaz Mahmod's boyfriend.
More than 25 women in Britain have been killed by their Muslim relatives in the past decade for offences they believe have brought shame on their family. More than 100 other homicides are under investigation for potential honour killings.
Some Muslim communities in Britain practice Sharia law, or strict Islamic law.
"We're seeing an increase around the world, due in part to the rise in Islamic fundamentalism," said Diana Nammi with the London-based Iranian and Kurdish Women's Rights Organisation.
During the three-month trial over Banaz Mahmod's murder, prosecutors said the girl's father began beating her at an early age for using hairspray and becoming too westernised.
Her uncle once told her that she would already have been "turned to ashes" if she were his daughter and had shamed the family by becoming involved with the Iranian Kurd, her sister 22-year-old Bekhal Mahmod testified.
Banaz Mahmod ran away from home when she was a teenager, but was later sent an audio tape in which her father warned he would kill her sisters, her mother and himself if she did not come home, her sister said.She returned home and was later hospitalised after her brother attacked her, her sister testified. The brother said he had been paid by their father to finish her off, but in the end was unable to do it, but in the end was unable to do it, the sister said, testifying in a full black burqa. She said she still feared for her life.
The years of Banaz Mahmod's abuse were compounded by officers who repeatedly dismissed her cries for help.
She first went to police in December 2005 when she suspected her uncle was trying to kill her and her boyfriend. She sent the police a letter naming the men who she thought would later kill her.
On New Year's Eve, she was lured by her father to her grandmother's home and believed she would be attacked after he forced her to gulp down brandy and approached her while wearing gloves. She escaped by breaking a window, and was treated at a hospital.
Police dismissed her claims. One officer, who is under investigation, considered charging her with damages for breaking her grandmother's window.
Laying in her hospital bed after the escape, Banaz Mahmod recorded a dramatic video message saying she was "really scared".
The videotape, taken by her boyfriend at the hospital, was shown to the jury during the trial. The boyfriend feared it could be the only chance she would have to detail her fears.
After she was released from the hospital, she returned home and tried to convince her family she stopped seeing her boyfriend, according to court documents.
But friends told the family they spotted the couple together on January 22, 2006.
Soon after, a group of men allegedly approached her boyfriend and tried to lure him into a car but he refused. It was that event that prompted Banaz Mahmod to go to police again. This time officers tried to persuade her to stay in a safe house. She refused, believing her mother would protect her, according to court documents.
But her mother and father left her alone in the house the next day. Her boyfriend - who noted the absence of text messages - quickly alerted police.
Her body was not discovered until three months later, after police tracked phone records.
One of the men who fled the country is allegedly the man who arranged for her burial in the northern city of Birmingham.
Bagelblogger: I can't be bothered to even try to keep the PC line here. What sort of twisted culture places honor in killing a daughter but approves a father threatening to kill her sisters, her mother and himself if she did not come home.
Despite protestations from the Muslim community, murders such as these would not occur if the particular communities involved weren't at least complicit in them through lack of action, and denouncement.
SMH: Father orders daughters brutal death
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