A former royal butler who opened doors for the Queen downloaded obscene images of young children, including scenes of torture and babies just months old.
More than 450 images of children were found on Greaves' laptop
Nicholas Greaves, 33, worked as an under-butler at Buckingham Palace between 2002 and 2004. He was jailed for two years at York Crown Court.
Judge Geoffrey Marson QC said the depravity the children would have been subjected to "beggars belief".
Greaves, of Crescent Avenue, Whitby, admitted distributing obscene images.
Police found 458 indecent photographs and 15 indecent films of children stored on his laptop computer when they raided his flat in Whitby.
The court heard 13 of the images were classed as the most serious level of depravity and included some images of torture.
The children in the pictures were girls and boys aged from babies who were just a few months old to 16 year olds.
He admitted five counts of distributing indecent photographs of children, three counts of possession of indecent photographs of children with intent to distribute, eight counts of having indecent photographs of children and one count of failing to surrender to bail.
Greaves had claimed he had no interest in the content of the photographs, but instead in the people who sent them to him.
Judge Marson said: "The reality is that, because you downloaded them as you did and distributed them as you did, you contributed to the degradation of these young children.
"Were it not for people like you, those who make and distribute these dreadful images would have no market for them."
After leaving his full-time position with the Royal family in June 2004, Greaves became butler to the Jordanian royal family in Belgravia, serving the King.
After returning to the UK he worked for the Royal family on a temporary basis for major occasions, including the Queen's 80th birthday.
Outside court, Det Sgt Darren Knight of North Yorkshire Police, said: "It's clear that he's a person who had some standing in society and who valued that standing.
"This whole investigation has brought his world crashing down around him. Personally, I can feel little sympathy for him."
He was disqualified from working with children for life and placed on the sex offenders' register at the hearing on Thursday.