John Huss

David S. Schaff's biography of the Czech priest Jan Hus - whose name is commonly anglicized as John Huss - is eye-opening and detailed, shedding light upon the philosophy and conflicts which led to Huss's execution.
Born into an era of immense religious fervor, Huss quickly distinguished himself with a commitment to Christian studies. His youth was spent singing in churches, where he made a subsistence income from donations. His intellectual abilities proven, he was an early attendant of the University of Prague where he acquired degrees. He quickly translated writings of John Wyclif, who himself (illegally in church law) translated the Bible to Middle English.
Perceiving immorality on the part of certain clerics, priests and bishops, Huss publicly condemned and ridiculed these moral failings. Events took a tumultuous turn when the Papal schism resulted in two claims for the Papacy, which threw the Catholic church into chaos. Huss's criticisms grew, and so did the number of enemies he had in the church.