The court found former Chad president Hissene Habre guilty of killing and torturing thousands of political opponents.
It's a historic judgement that completes a 16-year fight to bring a tyrant to justice.
Hissene Habre has been convicted on African soil for crimes against humanity committed during his brutal eight-year rule of the impoverished nation of Chad.
The former President - ousted in a 1990 coup - was also found guilty of rape by a special court, in a verdict that's sparked celebrations on the streets of the country's capital, N'Djamena.
"I am very satisfied with the verdict. Hissene Habre being sentenced to life in jail is just fine with me. I didn't expect to feel such joy but today I am very happy......"
"It's a historic day for Chad and for Africa. It's a great first to condemn an African head of state and especially a dictator. That will be a lesson to other dictators in Africa who are still there to impose dictatorship."
Souleymane Guengueng spoke on behalf of victims after the verdict was announced.
"I do not have the words, but let the name of God alone be glorified. It hurts me that many of my colleagues died along the way. They could not be here to see these result, which is why I was moved and brought to tears, but it is still a truly happy moment. I've said it, but I cannot say it enough, Hissene Habre was sentenced to life imprisonment. He will finish off his life in prison, and that's all we wanted."
At the trial in the Senegal capital, Dakar, he and other victims testified about the suffering they endured.
"Joswe" was one of them.
He had drawn pictures of torture techniques for the judges.
"When I look at these drawings it's like I am feeling the evils again. I feel it in my bones. When I draw this spot I remember how they climbed on my back and shouted 'savage, you can just die'. When I draw I am reminded of what a shock this was and how mean these people were. They enjoyed hearing us scream. It's unbelievable."
The ruling by an African Union-backed tribunal is the first time in modern history one country's domestic court has prosecuted another's former leader on human rights abuses.
It's also significant because it comes at a time when nations on the continent have been arguing they - rather than just the International Criminal Court - should be free to charge their own.
According to Human Rights Watch researcher, Reed Brody, it sends a powerful warning to dictators that if they commit atrocities they will never be safe from their victims.
"The fact that Hissene Habre was condemned not only for crimes against humanity, torture, and war crimes, but also for sexual crimes, sexual slavery, and for having perpetrated the rape of a woman, shows that no leader, no matter how powerful he is, is above the law and that no woman, no girl, is below the law."
Todd Buchwald is the US State Department Global Criminal Justice Coordinator.
He's welcomed the verdict against a leader once feted at the White House in Washington by former US President Ronald Reagan in 1987 after expelling Libyan forces from Chad.
"I think it's an encouraging moment, and I think that this day wouldn't have been possible without the cooperation of Chad, of Senegal, who just hosted this, it is not an easy thing to do, and of the African Union, and that is an encouraging thing for sure."
Habre had refused to recognise Senegal's right to try him and was initially dragged into the court by soldiers.
His lawyer, Ibrahima Diawara, has condemned the verdict.
"We are quite disappointed because with everything that had been achieved throughout the trial proceedings and the way we've proved the innocence of president Habre who was faced with faulty accusations that could not be proved, we were expecting a verdict of acquittal."
The 73 year-old's legal team has two weeks to launch an appeal.
