By this provisional arrangement the Empire was divided into “circles.” The episcopal duchy of Cambrai, Liège, and the small principality of Stavelot-Malmedy became a part of the so-called circle of Westphalia; the Seventeen Provinces of the Netherlands and the Franche-Comté constituted a new circle, called the “circle of Bourgogne.” These states were placed under the armed protection of the Empire, which undertook to defend them as members of the whole. They were recognized, however, as independent and free states, not subject to the laws of the Empire. At the same time, fearing that, through the application of the varying rules of succession existing in each Belgian principality, the union might some day become imperiled, Charles V, by a special act, ordained that the Netherlands or Seventeen Provinces should forever be considered an indivisible whole, in which the first-born son should be regarded as the heir to the throne. In case of deficiency of a male heir, however, the female heir was to be recognized in the succession. This was really a constitutional law sanctioned by the States-General, officially gathered in solemn meeting in Brussels in 1549. The early work of the dukes of Burgundy was now completed and firmly established. Another task of tremendous importance now engaged the attention of Charles. This was the fight against heresy. The new difficulty presented an entirely novel problem. When, by the revolt of Luther against the Roman Catholic church, Protestantism began rapidly to spread all over Europe, it quickly found a follower in the Netherlands, whose location facilitated its expansion. In virtue of their historical development, the Netherlands are an essentially Catholic state. Charles V and Philip II, as sovereigns of that state, considered themselves the defenders of orthodoxy, religious unity, and the union of church and state. In opposing what they considered to be a political as well as a religious crime, they invoked the penal laws and criminal institutions as their weapons against what they regarded as a revolutionary movement. The famous _placarts_, or penal laws, enacted under Charles V to the number of a dozen between 1520 and 1530, were complementary to each other. They were all the work of the government and were approved by the States-General, the prominent members of the military aristocracy, and the knights of the Golden Fleece. They were preventive and repressive at the same time. From a repressive point of view, they distinguished between the crime of heresy and the simple offense against the prescriptions of the _placarts_.