The 30 Years War: Catholics vs. Protestants

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Religious Warfare Across Europe During the Reformation

You're on a roll. Keep up the good work!

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 1:47 The Bohemian Phase
  • 3:16 The Danish Phase
  • 4:38 The Swedish Phase
  • 5:58 The French Phase
  • 7:17 End of War
  • 8:31 Lesson Summary
Save Save Save

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Log in or Sign up

Speed Speed

Recommended Lessons and Courses for You

Lesson Transcript
Instructor: Jessica Whittemore

Jessica has taught junior high history and college seminar courses. She has a master's degree in education.

This lesson will explore the reasons for the 30 Years' War. It will highlight the different phases of the war while also explaining why most of Europe took up battle against the Holy Roman Empire and the Hapsburg Dynasty.

The Holy Roman Empire

The 30 Years' War, which took place in the first half of the 17th century, is one of the most devastating wars in European history. Though the war took place mainly within modern-day Germany, many of Europe's nations were involved.

Like many wars of its time period, the 30 Years' War had its root in politics and religion. From the religious point of view, this war was the Catholic attempt to overcome Protestantism. On the political side, it was the Hapsburg Dynasty's attempt to keep control while many other countries worked to rob them of it.

As we study this continent-consuming conflict, it's important to note I'll use the terms Hapsburg Dynasty and Holy Roman Empire interchangeably. I'll do this simply because the Hapsburgs dominated the Holy Roman Empire at the onset of the war. For those of you who are unfamiliar with the Holy Roman Empire, it consisted of Central Europe. Although parts of Italy and Hungary were under its control, its center of power was the areas of Germany and Austria.

Since the 30 Years' War included so many countries warring against the Holy Roman Empire, it is usually divided into four phases. Since this war was an epic fight for power, we'll call these phases rounds. They'll be Round 1: The Bohemian Phase, Round 2: The Danish Phase, Round 3: The Swedish Phase, and Round 4: The French Phase. By the time we're finished, we'll understand why the 30 Years' War was one of the most devastating conflicts of European history.

Round #1 - The Bohemian Phase

The first round of the 30 Years' War pitted Bohemia against the Holy Roman Empire and a few of its German states. Unfortunately for the Bohemians, they were outnumbered from the start.

Ferdinand II was determined to take away power from the Protestants in Bohemia.
Ferdinand II Portrait

In 1617, Ferdinand of the staunchly Catholic Hapsburg Dynasty took the throne of Bohemia, now the modern-day Czech Republic. Upon taking the throne, he moved to weaken the power of Protestantism within the land. This quickly angered the members of the Bohemian nobility, who were mostly of the Protestant faith. In 1618, the Protestant Bohemian revolt began when Protestant rebels threw a few Catholic officials from the window of a government building. Surprisingly, the royal officials were not seriously injured. However, this incident, which became known as the Defenestration of Prague, marked the opening of the 30 Years' War. To quell the rebellion, Ferdinand, also known as the Holy Roman Emperor Ferdinand II, enlisted the help of his German states. However, only the states that were loyal to Catholicism joined the fight. The Holy Roman Empire and the Catholic states invaded Bohemia and squelched the rebellion. With this, the Bohemian phase of the 30 Years' War ended in a victory for Catholicism and the Hapsburgs of the Holy Roman Empire.

Round #2 - The Danish Phase

The Danish phase of the 30 Years' War saw the Holy Roman Empire mixing it up with Denmark. Christian IV, Denmark's Protestant king, felt Ferdinand II was a threat to Protestants everywhere. In 1625, Christian IV went to war against the Empire. This time, the German states loyal to Protestantism joined Denmark's cause. Adding to this, France got in on the action by financially backing Denmark.

France's willingness to financially back Protestant Denmark signaled a shift in the 30 Years' War. France was a Catholic nation who had no desire to see Protestantism grow. However, since they disliked the Hapsburg Dynasty even more than they disliked Protestants, they supported the Protestants in order to curb Hapsburg power. In other words, their motivation was political, not religious.

Backed by German Protestants and money from France, the Danish Protestants made some headway. However, the Empire struck back, sweeping through Germany and handing the Protestants a defeat. Although Christian IV was able to keep Denmark, the Danish Phase of the 30 Years' War ended in another victory for Catholicism and the Hapsburgs.

Round #3 - The Swedish Phase

The Hapsburg victories over Bohemia and Denmark scared Protestants all across Europe. Afraid of where the Hapsburgs might strike next, Sweden decided to go on the offensive. In 1630, Swedish troops moved into Germany. They were aided by the remaining German Protestants. Adding to this, France again threw its financial support behind Protestant Sweden.

Sweden invaded Germany with the help of German Protestants and money from France.
Sweden Invaded Germany with Help

During the early stages of the conflict, the Swedes won several notable victories. However, when Sweden's king was killed in battle, the Protestant forces fell into confusion. This gave the Holy Roman Empire the chance to make up for lost ground. When the Empire dealt the Swedes a decisive defeat in southern Germany, both sides met to negotiate peace. In 1635, the Swedish phase came to an end with the Peace of Prague. Within this peace treaty, three main things were established. First, it offered protection to Protestants living in northern Germany. Oddly, this didn't extend to the Protestants in the south. Second, it combined the armies of the Holy Roman Empire and the German states into one. Third, it forbade German princes to ally with each other or any foreign power.

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account