DAKAR - An expert strategist in desert warfare, Chad's Hissene Habre seized power in 1982 and quickly assumed the role of remorseless dictator, with brutal repression the hallmark of his eight-year reign.
Typically dressed in combat fatigues, which earned him the nickname "desert fighter", he fled to Senegal after he was ousted in 1990 by Chad's current President Idriss Deby.
Now 72, Habre's rule was marked by fierce crackdowns on dissent, including alleged torture and executions of opponents, earning him comparisons with ruthless Chilean dictator Augusto Pinochet.
An official truth commission report in 1992 accused his regime of committing some 40,000 political murders - although only 4,000 victims were officially named.
He goes on trial in Dakar on Monday for crimes against humanity, war crimes and torture after spending two years on remand.
The son of a farmer, Habre was born in 1942 in Faya-Largeau, northern Chad, and grew up among nomads in the Djourab desert.
His intelligence won him a job as a local official before he left for Paris in 1963 to study law and attend Sciences-Po, the city's prestigious political science school.
Returning home in 1971, he joined the Chad National Liberation Front a year later and became its leader, before breaking away to form another rebel group, the Northern Armed Forces (FAN).
Habre made international headlines in 1974 when he kidnapped a French ethnologist for three years, forcing France to negotiate for the hostage.
A staunch nationalist, Habre then went on to serve as prime minister in the government of president Felix Malloum and as defence minister under his sometime ally and later president Goukouni Weddeye.
Habre, unlike Weddeye, was an outspoken opponent of Libyan leader Moamer Kadhafi, and the relationship did not last.
Habre broke from his Tripoli-backed ally months after the formation of Weddeye's 1979 government, triggering a civil conflict in N'Djamena.
He was forced to flee the capital for eastern Chad in 1980, but returned to fight his way to power in 1982.
Pious, generous neighbour
During his rule opponents - real or perceived - were arrested, tortured and often executed by the Documentation and Security Directorate (DDS), Chad's feared secret police.
Habre's reign ended as dramatically as it had begun when Deby, one of his formerly loyal generals, led the rebels who drove him from power, forcing him to flee to Senegal.
The former dictator lived freely for over 20 years in an upmarket Dakar suburb with his wife and children, swapping his military garb for billowing white robes and a cap.
He was seen as a discreet, generous neighbour and a pious Muslim, known for his financial contributions to the construction of mosques.
American lawyer Reed Brody, the lead investigator into Habre's rule for Human Rights Watch, said the former dictator had taken the precaution of "emptying the coffers" before leaving Chad and built up a "protection network" in Senegal.
In his memoirs published last year, then-president Abdou Diouf says he had huge difficulty in persuading Habre to return to Chad the state-owned airplane that had brought him to Dakar.
The African Union had mandated Senegal to try Habre in July 2006, but the country delayed the process for years under former president Abdoulaye Wade, despite an agreement to create a special court to try him.
Habre was also wanted for trial in Belgium on war crimes and crimes against humanity charges after three Belgian nationals of Chadian origin filed suit in 2000 for arbitrary arrest, mass murder and torture during his regime.
Belgium issued an arrest warrant for him in September 2005, and he was arrested in Senegal shortly after, but the African country announced that its courts did not have competence to rule on a Belgian extradition request.
The AU decided the trial should take place in Senegal, which will make Habre the first African leader accused of atrocities to face justice in the continent rather than in an international court.