The Calvinists generally held meetings in the open air where they could escape the restrictions that were placed on services held in any place of worship. The middle and lower classes attended them in large numbers, and the new faith spread rapidly through the enlightened world of Western Europe. John Knox, the renowned Scotch preacher, was a firm friend of Calvin, and thundered denunciations from his Scotch pulpit at the young Queen Mary, who had come from France with all the levity of French court-training in her manners. The people of Southern France were eager to hear the fiery speech that somehow captured their imagination. As they increased in numbers and began to have political importance they became known as Huguenots or Confederates. To Catherine de Medici, the Catholic Regent of France, they were a formidable body, and in Navarre their leaders were drawn mainly from the nobles.

Relentless persecution would probably have crushed the Huguenots of France eventually if it had been equally severe in all cases. As a rule, men of the highest rank could evade punishment, and a few of the higher clergy preached religious toleration. Thousands marched cheerfully to death from among the ranks of humble citizens, for it was part of Calvin's creed that men ought to suffer martyrdom for their faith without offering resistance. Judges were known to die, stricken by remorse, and marvelling at their victims' fortitude. At Dijon, the executioner himself proclaimed at the foot of the scaffold that he had been converted.

The Calvinist preachers could gain no audience in Paris, where the University of the Sorbonne opposed their doctrines and declared that these were contrary to all the philosophy of ancient times. The capital of France constantly proclaimed loyalty to Rome by the pompous processions which filed out of its magnificent churches and paraded the streets to awe the mob, always swayed by the violence of fanatic priests. The Huguenots did not attempt to capture a stronghold, where it was boasted that "the novices of the convents and the priests' housekeepers could have driven them out with broomsticks."

Such rude weapons would have been ineffectual in the South-East of France, where all the most flourishing towns had embraced the reformed religion. The majority of the Huguenots were drawn from the most warlike, intelligent, and industrious of the population of these towns, but princes also adopted Calvinism, and the Bourbons of Navarre made their court a refuge for believers in the new religion.

Navarre was at this time a narrow strip of land on the French side of the Pyrenees, but her ruler was still a sovereign monarch and owed allegiance to no overlord. Henry, Prince of Bourbon and King of Navarre, was born in 1555 at Béarns, in the mountains. His mother was a Calvinist, and his early discipline was rigid. He ran barefoot with the village lads, learnt to climb like a chamois, and knew nothing more luxurious than the habits of a court which had become enamoured of simplicity. He was bewildered on his introduction to the shameless, intriguing circle of Catherine de Medici.

The Queen-Mother did not allow King Charles IX to have much share in the government of France at that period. She had an Italian love of dissimulation, and followed the methods of the rulers of petty Italian states in her policy, which was to play off one rival faction against another. Henry of Guise led the Catholic party against the Huguenots, whose leaders were Prince Louis de Bourbon and his uncle, the noble Admiral de Coligny. Guise was so determined to gain power that he actually asked the help of Spain in his attempt to crush the "heretics" of his own nation.

The Huguenots at that time had won many notable concessions from the Crown, which increased the bitter hostility of the Catholics. The Queen-Mother, however, concealed her annoyance when she saw the ladies of the court reading the New Testament instead of pagan poetry, or heard their voices chanting godly psalms rather than the old love-ballads. She did not object openly to the pious form of speech which was known as the "language of Canaan." She was a passionless woman, self-seeking but not revengeful, and adopted a certain degree of tolerance, no doubt, from her patriotic counsellor, L'Hôpital, who resembled the Prince of Orange in his character.

The Edict of January in 1562 gave countenance to Huguenot meetings throughout France, and was, therefore, detested by the Catholic party. The Duke of Guise went to dine one Sunday in the little town of Vassy, near his residence of Joinville. A band of armed retainers accompanied him and pushed their way into a barn where the Huguenots were holding service. A riot ensued, in which the Duke was struck, and his followers killed no less than sixty of the worshippers.

This outrage led to civil war, for the Protestants remembered bitterly that Guise had sworn never to take life in the cause of religion. They demanded the punishment of the offenders, and then took the field most valiantly. Gentlemen served at their own expense, but they were, in general, "better armed with courage than with corselets." They were overpowered by the numbers of the Catholic League, which had all the wealth of Church and State at its back, and also had control of the King and capital. One by one the heroic leaders fell. Louis de Bourbon was taken prisoner at Dreux, and Anthony of Bourbon died before the town of Rouen.