The man from Rwanda, who became a Swedish citizen in 2012, was sentenced to life in prison by Stockholm district court last May for his role in the genocide in the African country. The 61-year-old, who denied the crimes, was found guilty of genocide and gross violation of international law, including murder, attempted murder and kidnapping.
He was said to have led mobs which clubbed, stabbed and shot to death thousands of men, women and children in Butare in southern Rwanda. The district court trial involved over 50 witnesses and judges travelling to Rwanda.
The orginal guilty verdict was upheld on Wednesday at the Svea Court of Appeal.
"We have waited a long time for this, the trial stopped in November but finally today we got the verdict, so I feel relieved," chief prosecutor Tora Holst tells Radio Sweden.
The man was ordered to pay a total of 81 million Rwandan francs (about USD 110,000) in damages to 15 plaintiffs who survived the attacks or whose close relatives were killed.
It is the second time a genocide trial has been held in Sweden.
Never before has a Swedish court awarded damages for victims of acts of genocide," the court said in a statement.
The International prosecution chamber in Stockholm is currently working on a third case involving genocide in Rwanda.
Some 800,000 people, mostly ethnic Tutsis, were killed by Hutu extremists during the Rwandan genocide, according to the UN.