The Protestant Reformation shattered the religious unity of Europe, leading to over a century of devastating warfare.

The French Wars of Religion (1562-1598) pitted Catholics against French Protestants (Huguenots).

The St. Bartholomew's Day Massacre in 1572 was a notorious event in which thousands of Huguenots were killed.

The Dutch Revolt, or Eighty Years' War (1568-1648), was a struggle for independence by the Protestant Netherlands against their Catholic Spanish rulers.

In 1588, Philip II of Spain launched the Spanish Armada in a failed attempt to invade Protestant England.

The Thirty Years' War (1618-1648), centered in the Holy Roman Empire, was the most destructive of these conflicts.

The Thirty Years' War began as a religious conflict but evolved into a political struggle over the balance of power in Europe.

The Peace of Westphalia in 1648 ended the Thirty Years' War.

This treaty established the modern principle of state sovereignty, where each state has authority over its own territory and domestic affairs.

The wars ultimately ended the era of enforcing religious uniformity by military force in Europe.