Shahid Mohammed has been jailed for life for murdering five children and three adults in an arson attack in Huddersfield in 2002.
Mohammed fled to Pakistan before a 2003 trial that saw several other people convicted for their role in the blaze targeting the Chisti family.
During the trial jurors heard the defendant held a grudge against the Chistis after his sister became involved with a man named Saud Pervez.
Mohammed did not approve of Mr Pervez, and was angry at one member of the Chisti family who had played an “active part” in maintaining the relationship.
Eight members of the Chisti family died in the blaze
Prosecutor Alistair MacDonald said the “carefully planned” attack saw Mohammed along with several other men throw petrol bombs into the Chisti’s family home and pour petrol into the house through a nozzle.
His lawyer Abbas Lakha had argued Mohammed had only acted as a lookout, and did not intend to throw anything.
Mohammed was extradited to the UK in October last year – he had been in a prison in Pakistan since January 2015.
Mohammed Shafique survived the fire along with his sister and father, and said he was emotional but “naturally pleased” that Mohammed Shahid had been brought to justice.
“This is not going to bring back our loved ones and I hope he gets a long prison sentence and I hope he doesn't see the light of day,” he said.
“It would have been nice for my father to be here, he passed away two years ago, and we missed him in this trial.”
Mohammed has been handed a life sentence with a minimum of 23 years.