This biographical sketch is part of the article:
Why the Reformation? (T&T 2001) by A E Bouter
Because of a royal marriage between King Richard II of England and Anne of Bohemia, Bohemian students went to Oxford to study. There, many accepted the ideas of Wycliffe and went back to propagate them in Bohemia.
One who accepted Wycliffe's ideas from these students was Jan Huss. He became a rector of the University of Prague in 1402. His preaching of Wycliffe's views contributed to a rise of nationalism among the Bohemians who chafed under the Holy Roman Empire and its close associate, the Roman Catholic Church.
Huss came under criticism from the Roman Church hierarchy and was summoned to appear before a church council in Constance, Switzerland. In spite of a written document of safe conduct to and from the council by the Holy Roman Emperor Sigismund, Huss was condemned as a heretic and publicly burned at the stake after seven months of incarceration and suffering. (Sigismund was told by the hierarchy it was all right to lie to a heretic).
Huss had proclaimed reform of the Roman Church along the lines of Wycliffe, appealing to the Bible, and rejecting papal absolutism. He was martyred, but his ideas lived on, found later in the Bohemian Brethren and in the Moravian Church. They also influenced Martin Luther.
Between 1409 and 1449, several church councils were convened in Western Europe in an attempt to reform the Roman Church from within. All failed in this objective, though they eventually healed the papal schism and got rid of some so-called heretics like Jan Huss. The failure to reform itself made the so-called Protestant Reformation inevitable as Western Europeans had increasing access to the Bible. After the printing press was invented, the first complete book printed in 1454 was the Bible.
 The main purpose of the council was to end the existing papal schism of three men claiming to be pope, and return to one pope located in Rome.