The detail
Jan Hus (c. 1370–1415), a Prague preacher and university master, drew on John Wyclif in criticising clerical wealth, the sale of indulgences and papal claims, and defined the Church as the body of the predestined. Summoned to the Council of Constance under a safe-conduct from Emperor Sigismund, he was tried, refused to recant propositions he said he had never held as charged, and was burned on 6 July 1415; his associate Jerome of Prague followed in 1416. In Bohemia these deaths were widely seen as a national and religious outrage.
The movement that followed is called Utraquist from sub utraque specie, "in both kinds", because its central sign was giving the cup as well as the bread to lay people, a practice begun in Prague in 1414. The Four Articles of Prague (1420) demanded communion in both kinds, free preaching, the end of clerical secular power and wealth, and the punishment of public sins. The movement had a moderate wing, close to traditional doctrine apart from the chalice, and radical wings such as the Taborites.
Five crusades were launched against the Hussites between 1420 and 1431 and all failed, under commanders like Jan Žižka. After the moderates defeated the Taborites at Lipany (1434), the Council of Basel agreed the Compacts (Compactata, 1436), allowing communion in both kinds in Bohemia and Moravia. Rome later refused to confirm them (Pius II, 1462), but the Utraquist church continued in practice until the 17th century.
In 1457, at Kunvald, a group inspired by the lay writer Petr Chelčický, who taught non-violence and separation from state power, formed the Unitas Fratrum (Unity of the Brethren). In 1467 it established its own ministry independent of Rome and of the Utraquists. After the Habsburg victory at White Mountain (1620) Protestantism in Bohemia was largely suppressed, and Bishop Jan Amos Comenius went into exile. Descendants of the Brethren found refuge on Count Zinzendorf's estate at Herrnhut in Saxony (from 1722), where the renewed Moravian Church dates its rebirth to 13 August 1727.
How each side tells it: Protestants often present Hus as a forerunner of the Reformation, and Luther wrote in 1520 that he and his allies were "all Hussites without knowing it". Czech national memory treats him as a hero. Catholic historiography long saw the movement as heresy and rebellion; in 1999 Pope John Paul II expressed "deep regret for the cruel death" of Hus, while not revising the council's doctrinal judgments. Historians stress that the Hussite movement was diverse and that its moderate wing differed from Rome mainly over the chalice, preaching and church reform.