Lammtarra, the unbeaten winner of the Derby, King George and Prix de l'Arc de Triomphe in 1995, has died at the age of 22.
Trained by the late Alex Scott as a two-year-old, he won the blue riband at Epsom in the care of Saeed bin Suroor after Scott was tragically murdered in September 1994, a month after the son of Nijinsky had won the Washington Singer at Newbury.
He raced in the name of Sheikh Mohammed's nephew Saeed Maktoum al Maktoum as a juvenile before being part of Godolphin in his Classic season, which saw him add the two all-aged middle-distance championships of Europe to his Epsom laurels.
The chestnut passed away in his sleep at Dalham Hall Stud on Sunday following a short illness.
Stud director Liam O'Rourke said: "Lammtarra was a horse very close to Sheikh Mohammed's heart. He was very intelligent, a true gentleman and never gave anyone a moment's trouble.
"Sadly, this was his time to go and we are pleased that he passed away comfortably. He will be missed by everyone here at Dalham."
From just four starts, Lammtarra earned over £1.25million in winning prize money.