Many conflicts arose during the Reformation. Some of them were small, while others were large and many people ended up getting killed.
The English Reformation
In England, King Henry VIII wanted the pope to end his marriage to Catherine of Aragon. The pope refused. As a result, Henry was furious and married another woman without the pope's permission. Then, he created his own religion called the Church of England and split off from the Cahtolic Church. The Act of Supremacy made the king head of the Church of England.

Warfare in Germany
In Germany, the Holy Roman Emperor sided with the Catholic Chruch and tried to convert the Protestants. Soon, a war between the Catholics and Protestants arose. The war finally ended when the Peace of Ausburg was signed. It allowed the ruler of Germany to choose which would be the country religion. However, this only split the country into independent regions each with their own religious traditions.

Signing of the Peace of Ausburg
Civil War in France
In France, the Huguenots (French Protestants) were able to worship freely at first. However, after they protested about the Catholic Church, many were killed, starting a civil war between the Catholics and the Protestants. The worst incident was St. Bartholemew's Day Massacre. Almost 3,000 Huguenots were murdered. Henry of Navarre soon became king and was crowned Henry IV. He converted from Protestantism to Catholicism to help unite the country and declared the Edict of Nantes, which allowed Huguenots to practice their religion freely.

The Spanish Inquisition
Philip II of Spain created an Inquistion against Protestants. He soon took control o Netherlands, which was a mainly Calvinist country. He sent troops to convert the Protestants. However, he only regained control of some of the Netherlands because Queen Elizabeth I of England had supported the Netherlands. As a result, King Philip II was furious and sent an armada to invade England, but the armada was easily destroyed.

English and Spanish armadas fighting at sea
The Thirty Years' War
During the Thirty Years' War, the Holy Roman Emperor fought against many Protestants in Prague, a city that is now part of the Czech Republic. Many other countries joined the war and supported Prague including France, Denmark, and Sweden. Soon, they stormed Germany, the country of the Holy Roman Emperor, and the Peace of Westphalia finally ended the war, which allowed people to practice whatever religion they wanted to.

A battle during the Thirty Years' War