Jan Hus travelled to Constance with a safe conduct from the emperor Sigismund, expecting a hearing on the reforming case he had been preaching in Prague. He was arrested within weeks, held for months in poor conditions, and given a trial in which he was required to abjure articles drawn from his writings, several of which he denied holding. He refused to abjure opinions he did not hold and refused to abjure those he did, and he was condemned and burned on 6 July 1415; his ashes were thrown into the Rhine so that nothing could be gathered as a relic. His colleague Jerome of Prague was burned the following year.
The council also condemned the teaching of John Wycliffe, dead thirty years, and ordered his remains dug up and burned. The safe conduct question was answered at the time with the argument that no promise made to a heretic could bind, a position that did more damage to the reputation of the council than any of its decrees did good.
In Bohemia the execution turned a reforming movement into a national one, and the Hussite wars began within four years. In 1999 John Paul II expressed deep regret for the cruel death inflicted on Hus, at a symposium held in Rome, without reversing the condemnation itself, and the Czech churches continue to mark 6 July.