The religious wars had afforded a great opportunity to the nobles of asserting their independence. Many of them had embraced Calvinism, and so gained for their disintegrating aspirations a religious sanction and a political ideal. It is said that by the Edict of Nantes Calvinistic worship was legalised in 3500 castles. Faction is ever strong when the Crown is weak, and Henry IV. had to buy the doubtful allegiance of many of the smaller nobles by sheer bribery, before he could establish himself upon the throne. But no sooner had he made his position secure than the nobles found that they had a master. They might be courtiers but not politicians. Henry deliberately intrusted the affairs of government to men of business of inferior rank, dependent on himself, and jealous of the nobles. Rigid inquiry was made into the privileges claimed by the nobles, and those which could not be substantiated were rescinded. The institution of the _paulette_ was intended to create a noblesse of the robe as a counterpoise to the noblesse of the sword. Duelling, that much-loved privilege of a gentleman, was absolutely forbidden, and the issue of letters of pardon to those who killed their adversary in a duel stopped. The nobles, accustomed to the licence of civil war, soon grew restive under the strong hand of Henry. [Sidenote: =The conspiracy of Biron, 1602.=] The maréchal de Biron, on the part of the Catholics, and the duc de Bouillon, the leader of the Huguenots, permitted themselves to enter into relations with Savoy and Spain, and to talk somewhat vaguely of a partition of France, in a way which was incompatible with loyalty to the king. When Henry struck he struck hard. The thirty-two wounds which Biron had received in the service of France failed to obtain his pardon. In 1602 he was executed, and his death gave the signal for the beginning of that war of revenge on the part of the Crown against the nobles, which was carried on with such relentless severity by Richelieu, and did not cease until the triumph of the Crown was assured under Louis XIV. The duc de Bouillon escaped to Germany, the comte d’Auvergne was imprisoned, the duc d’Epernon, frightened into submission, was pardoned. Perhaps Henry himself hardly dared to touch the former companion of Henry III., the governor of half France, and the proudest of all her proud nobility. Four years afterwards the vengeance of Henry was still awake though all the excitement and danger had long ago quieted down. In 1606 he travelled through the disaffected districts of the south and south-west accompanied by an army, destroyed several castles belonging to the nobles, and put to death, after sentences by special tribunals, those who had taken a prominent part in the late troubles. [Illustration: MAP SHOWING THE TERRITORIAL GAINS OF FRANCE IN THE 17th CENTURY.]