Religious differences led to riots, civil wars, and international conflicts in Europe during the sixteenth century. The first battleground was Switzerland, where in the 1520s and 1530s Protestants and Catholics fought one another until both sides decided that a treaty was preferable to further fighting. The treaty allowed each part of Switzerland to determine its own religion and ordered each side to give up its foreign alliances, a policy of neutrality that has characterized Switzerland ever since.
In the Holy Roman Empire fighting began in 1546. The empire was a confederation of hundreds of principalities, independent cities, duchies, and other polities loosely united under an elected emperor. The initial success of Emperor Charles V led to French intervention on the side of the Protestants, lest the emperor acquire even more power. In 1555 Charles agreed to the Peace of Augsburg, which officially recognized Lutheranism and ended religious war in Germany for many decades. Under this treaty, the political authority in each territory of the Holy Roman Empire was permitted to decide whether the territory would be Catholic or Lutheran. Most of northern and central Germany became Lutheran, while southern Germany was divided between Lutheran and Catholic. His hope of uniting his empire under a single church dashed, Charles V abdicated in 1556, transferring power over his Spanish and Dutch holdings to his son Philip II and his imperial power to his brother Ferdinand.
In France Calvinists and Catholics each believed that the other’s books, services, and ministers polluted the community. Armed clashes between Catholic royalists and Calvinist antiroyalists occurred in many parts of France. A savage Catholic attack on Calvinists in Paris on August 24, 1572 — Saint Bartholomew’s Day — occurred at the marriage of the king’s sister Margaret of Valois to the Protestant Henry of Navarre, which had been intended to help reconcile Catholics and Huguenots. The Saint Bartholomew’s Day massacre initiated a civil war that dragged on for fifteen years, destroying agriculture and commercial life in many areas.
In the Netherlands the movement for church reform developed into a struggle for Dutch independence. In the 1560s Spanish authorities attempted to suppress Calvinist worship and raised taxes. Civil war broke out from 1568 to 1578 between Catholics and Protestants in the Netherlands and between the provinces of the Netherlands and Spain. Eventually the ten southern provinces — the Spanish Netherlands (the future Belgium) — came under the control of the Spanish Habsburg forces. The seven northern provinces, led by Holland, formed the Union of Utrecht (United Provinces of the Netherlands) and in 1581 declared their independence from Spain. The north was Protestant, and the south remained Catholic. Hostilities continued until 1609, when Spain agreed to a truce that recognized the independence of the northern provinces.
The era of religious wars was also the time of the most extensive witch persecutions in European history, as authorities tried to rid their cities and states of people they regarded as linked to the Devil. Both Protestants and Catholics tried and executed those accused of being witches, with church officials and secular authorities acting together. The heightened sense of God’s power and divine wrath in the Reformation era was an important factor in the witch-