* Harris showed no remorse for harm to his victims, judge says
* Biggest name to face trial so far in "Operation Yewtree" probe into UK celebrities
* Five decades at pinnacle of show business (Adds reaction, background)
By Costas Pitas
LONDON, July 4 (Reuters) - Veteran entertainer Rolf Harris, a household name in his native Australia and adopted home Britain, was jailed for almost six years on Friday for repeatedly abusing young girls during decades as a beloved host of children's television.
Handing down the sentence, Judge Nigel Sweeney said the 84-year-old host of shows like "Rolf Harris Cartoon Time" had shown no remorse for the harm he had done to his victims.
Harris was found guilty earlier this week of 12 counts of assaulting four girls, some as young as seven or eight, between 1968 and 1986.
It was the second conviction in a long-running investigation into sex abuse by British celebrities that has led to soul searching in the country, revealing that some of its most prominent stars of the 1970s and 1980s were serial paedophiles who evaded detection for decades.
"It is clear from the evidence that what you did has had a significant adverse effect on each victim," the judge told Harris, detailing how one woman had battled with alcoholism as a direct result of his abuse.
"You have shown no remorse for your crimes at all."
An artist and musician who first earned fame in the 1950s with the top 10 hit novelty song "Tie Me Kangaroo Down, Sport", Harris went on to present prime-time TV shows mostly aimed at children during five decades at the pinnacle of show business. In 2005 he painted Queen Elizabeth's portrait.
Harris was the biggest name to go on trial since British police launched "Operation Yewtree" to investigate celebrity child abuse, following revelations that late BBC TV host Jimmy Savile had been a prolific child abuser.
Harris sat motionless as the judge read out the sentence at a packed courtroom at London's Southwark Crown Court. He was later led from the dock, wearing a grey suit, white shirt and multi-coloured tie.
During the trial, the prosecution had portrayed the bearded, bespectacled entertainer as a predator who groomed and abused one woman for her entire teenage and young-adult life.
The London court was told he first assaulted the woman when she got out of the shower aged 13, and then repeatedly abused her until she was 28 years old.
Police launched Operation Yewtree in the wake of the disclosures that Savile, who died in 2011 at 84, had managed to escape detection while abusing hundreds of children over the course of decades as one of Britain's best known celebrities, using his fame to gain access to victims and deflect suspicion.
Since then, a dozen ageing British media luminaries have been the target of investigations over decades-old child abuse allegations.
The country's most well known publicist, Max Clifford, was found guilty in May of indecently assaulting teenage girls some 30 years ago as part of the investigation. (Writing by Kate Holton; Editing by Peter Graff)