He was a monster even by the standards of Saddam Hussein's Iraq, a sadist with a taste for cruelty so extreme that even his father was forced to acknowledge that his first-born son would not be a worthy heir.

And yet for all that Uday Saddam Hussein symbolised the brutality of the Iraqi regime, his powers were severely circumscribed. Although he retained the privileges of the much-indulged son of a dictator, he was shunted from the real centres of power in the military and security services by his quieter, younger brother Qusay.

Although Uday nominally had a role in politics - following his election to parliament with 99% of the vote in 1999 - he was studiously absent from Iraqi television during the dying days of the regime.

It was clear controllers realised that showing too many pictures of the most hated man in Iraq was hardly going to spur resistance.

It was not the life that Uday had intended. Of Saddam's two sons, he was the flamboyant one - towering well over 6ft, with a penchant for fast cars and loud and drunken parties, expensive suits and flowing robes, as well as murder, rape and torture.

His public duties ranged from the Iraqi Olympic Committee and the national football team, to Babel, supposedly an independent newspaper, and Shabab, or youth television, to the Iraqi Photographers' Association. He also was in charge of the dreaded Saddam Fedayeen militia.

For those unfortunate enough to have strayed across his path, Uday's reasons for taking on such a public life were pathetic: he wanted to build a public profile in preparation for taking over from Saddam.

The search for public approbation appears to have taken over in the mid-1980s when Uday first took a close interest in sport. Footballers say he never really understood or showed much interest in the game itself, but was desperate enough for a win that he would phone up the dressing room during half-time to threaten to cut off players' legs and throw them to ravenous dogs.

As football overseer, Uday kept a private torture scorecard, with written instructions on how many times each player should be beaten on the soles of his feet after a particularly poor showing.

He also carried a grudge. "Once you came to Uday's notice, he never left you alone. The only time I managed to get away from his eyes was when I went outside Iraq," star performer Habib Jaffar told the Guardian last April.

Uday's excesses carried over in his private life where he had a reputation for ordering any girl or woman who caught his eye to be brought to his private pleasure dome.

The palace, a bad taste Arabian nights fantasy, was decorated with indoor fountains and erotic murals and was in the grounds of his father's presidential estate. A nearby chamber contained huge stashes of drugs as well as an HIV testing kit, according to US forces.

He is also reported to have operated an even more private torture chamber on the banks of the Tigris.

But his brutality finally caught up with him. In 1988 he bludgeoned to death his father's bodyguard Kamal Hana Jajo in front of horrified partygoers.

He also shot one of his uncles in the leg. The murder, shootings, and other erratic behaviour put him in permanent disfavour with Saddam. He was briefly exiled to Switzerland and, while he was allowed to return to Iraq, he was never again deemed suitable for succession.

Uday's marriages were a further source of embarrassment to his father.

His two brief dynastic liaisons - with the daughters of a senior Ba'ath party aide of Saddam and an uncle - were dissolved after Uday beat up his brides.

His remove from power grew even greater in 1996 when gunmen fired on his red Porsche as it sped through the streets of Baghdad. The attack left the scion of Saddam able to walk only with great difficulty.

It also appears to have deepened his rage against his fellow Iraqis. Sports figures in Iraq say he had come to see his duties at the Olympic committee only as a source of ready cash. His cruelty, already legendary, deepened.