On October 26 1440, Gilles de Rais was brought to the main place in Nantes, to be strangled and burnt with his two associates, Griart and Poitou.

But before he died, he sang the De Profundis in a voice louder than all the rest while standing under the gibbet. He urged his henchmen to "thank God with him for a manifest sign of His love," and to continue praying for a little while longer.

He prayed on his knees, and the hundreds of spectators prayed with him. In his agonies of guilt, he said to the families of the murdered:

“You who are present--you, above all, whose children I have slain--I am your brother in Christ. By Our Lord's Passion, I implore you, pray for me. Forgive me with all your hearts the evil I have done you, as you yourselves hope for God's mercy and pardon”.

When de Rais was theatrically executed, the children's parents, his judges, and hundreds of spectators, gave way to floods of tears. His fellow criminals followed soon after.

His corpse was placed on a pyre, but his relatives were allowed to remove his body before the flames reached it, and he was interred in the nearby Carmelite church. His two companions were less lucky; they were burned alive.

The precise number of Rais's infanticides is not known, as most of the bodies were burned or buried. The number of murders is generally placed between 80 and 200; a few have conjectured numbers upwards of 600. The victims ranged in age from six to eighteen and included both sexes; although Rais preferred boys, he would make do with young girls if circumstances required.

It is important to note here that Gilles was not allowed any testimony in his defence, nor was he given any legal advice or council. The proceedings of the trial were highly irregular, even for trials of heresy. Not one of his 500 servants was summoned to give defensive evidence and his own attendants were tortured and, having testified against Gilles, freed. This treatment is consistent with how the ecclesiastical courts handled witches and heretic trials during this time. Some historians have alleged that Rais was framed for murder and heresy by elements within the Church as part of a diocesan plot to seize his lands.