At a late stage of the conflict, the Utraquists changed sides in 1432 to fight alongside Roman Catholics and opposed the Taborites and other Hussite factions.

[1][2] Because Sigismund had plans to be crowned the Holy Roman Emperor (requiring papal coronation), he suppressed the religion of the Hussites, yet it continued to spread.

[3] When King Wenceslaus IV of Bohemia, brother of Sigismund, died of natural causes a few years later, the tension stemming from the Hussites grew stronger.

Starting around 1402, priest and scholar Jan Hus denounced what he judged as the corruption of the church and the papacy, and he promoted some of the reformist ideas of English theologian John Wycliffe.

In 1411, in the course of the Western Schism, "Antipope" John XXIII proclaimed a "crusade" against King Ladislaus of Naples, the protector of rival Pope Gregory XII.

The knights and nobles of Bohemia and Moravia, who were in favour of church reform, sent the protestatio Bohemorum to the Council of Constance on 2 September 1415, which condemned the execution of Hus in the strongest language.

The more extreme Hussites became known as Taborites (Táborité), after the town of Tábor, which became their centre; or Orphans (Sirotci), a name they adopted after the death of their leader and general Jan Žižka.

Wenceslaus's widow Sophia of Bavaria, acting as regent in Bohemia, hurriedly collected a force of mercenaries and tried to gain control of Prague, which led to severe fighting.

The nobles, sympathetic to the Hussite cause, but supporting the regent, promised to act as mediators with Sigismund, while the citizens of Prague consented to restore to the royal forces the castle of Vyšehrad, which had fallen into their hands.

Weight, lack of accuracy and cumbersome use of early types limited their employment to static operations and prevented wider use in open battlefield or by civilian individuals.

The main weight of the fighting rested on militiamen armed with cold weapons, but firearms shooting from behind the safety of the wagon forts proved to be very effective.

[5] The year 1421 marked not only a shift in the importance of firearms, from auxiliary to primary weapons of Hussite militia, but also the establishment of the Čáslav diet of formal legal duty for all inhabitants to obey the call to arms of the elected provisional government.

[9] The name of a cannon used by the Hussites, the Czech: houfnice, gave rise to the English term, "howitzer" (houf meaning "crowd" for its intended use of shooting stone and iron shots against mass enemy forces).

A firm adherent of the Church of Rome, Sigismund was aided by Pope Martin V, who issued a bull on 17 March 1420 proclaiming a crusade "for the destruction of the Wycliffites, Hussites and all other heretics in Bohemia".

Sigismund and many German princes arrived before Prague on 30 June at the head of a vast army of crusaders from all parts of Europe, largely consisting of adventurers attracted by the hope of pillage.

The sacrament of the most Holy Eucharist shall be freely administered in the two kinds, that is bread and wine, to all the faithful in Christ who are not precluded by mortal sin – according to the word and disposition of Our Saviour.

All mortal sins, and in particular all public and other disorders, which are contrary to God's law shall in every rank of life be duly and judiciously prohibited and destroyed by those whose office it is.

[citation needed]These articles, which contain the essence of the Hussite doctrine, were rejected by King Sigismund, mainly through the influence of the papal legates, who considered them prejudicial to the authority of the pope.

At Prague, a demagogue, the priest Jan Želivský, for a time obtained almost unlimited authority over the lower classes of the townsmen, and at Tábor, a religious communistic movement (that of the so-called Adamites) was sternly suppressed by Žižka.

On his departure, civil war broke out, the Taborites opposing in arms the more moderate Utraquists, who at this period are also called by the chroniclers the "Praguers", as Prague was their principal stronghold.

On 27 April 1423, Žižka now again leading, the Taborites defeated the Utraquist army under Čeněk of Wartenberg at the Battle of Hořice; shortly afterwards an armistice was concluded at Konopilt.

Free for a time from foreign threat, the Hussites invaded Moravia, where a large part of the population favored their creed, but paralysed again by dissensions, they soon returned to Bohemia.

After several military successes gained by Žižka in 1423 and the following year, a treaty of peace between the Hussite factions was concluded on 13 September 1424 at Libeň, a village near Prague (now part of that city).

The Prussian historian Heinrich von Treitschke later wrote that they had "greeted the sea with a wild Czech song about God's warriors, and filled their water bottles with brine in token that the Baltic once more obeyed the Slavs.

The Roman See reluctantly consented to the presence of heretics at this council but indignantly rejected the suggestion of the Hussites that members of the Eastern Orthodox Church, and representatives of all Christian creeds, should also be present.

On 1 August 1431, a large army of crusaders under Frederick I, Elector of Brandenburg, accompanied by Cardinal Cesarini as papal legate, crossed the Bohemian border.

According to legend, upon seeing the Hussite banners and hearing their battle hymn "Ktož jsú boží bojovníci" ("Ye Who are Warriors of God"), the invading papal forces immediately took to flight.

[16]The Utraquist creed, frequently varying in its details, continued to be that of the established church of Bohemia until all non-Catholic religious services were prohibited shortly after the Battle of the White Mountain in 1620.

The Moravian Brethren (Unitas Fratrum) - whose intellectual originator was Petr Chelčický but whose actual founders were Brother Gregory, a nephew of Archbishop Rokycany, and Michael, curate of Žamberk – to a certain extent continued the Taborite traditions, and in the 15th and 16th centuries included most of the strongest opponents of Rome in Bohemia.

After the beginning of the German Reformation, many Utraquists adopted to a large extent the doctrines of Martin Luther and of John Calvin and, in 1567, obtained the repeal of the Compacts which no longer seemed sufficiently far-reaching.