After the Peace of Westphalia in 1648, European states stopped fighting mainly over religion and started organizing diplomacy and war around the balance of power, the idea that no single state should grow strong enough to control the others. When Louis XIV's France pushed too far, rival powers formed coalitions to check it, while professional armies, gunpowder weapons, and stronger state finances changed how European wars were fought.
Why This Matters for the AP European History Exam
Balance of power is one of the clearest examples of how diplomacy and warfare changed after 1648, so it shows up often in questions about causation and continuity and change. You can use it to explain why states formed shifting alliances, why some powers rose while others collapsed, and how the military revolution tied warfare to taxation and bureaucracy. These connections give you strong, specific evidence for argument-based writing and help you read primary sources about treaties, wars, and statecraft on the multiple-choice section.
Key Takeaways
- The Peace of Westphalia (1648) shifted European conflict away from religion and toward keeping any one state from gaining too much control.
- States formed temporary coalitions across old religious lines to block a rival's expansion, especially against Louis XIV's France.
- Louis XIV's nearly continuous wars (the Dutch War, the Nine Years' War, and the War of the Spanish Succession) provoked alliances meant to contain France.
- Weak or decentralized states declined: Poland was partitioned by Prussia, Russia, and Austria, and the Ottomans stopped expanding west after the 1683 Battle of Vienna.
- The military revolution, including infantry, firearms, mobile cannon, and stronger fortifications, favored states that could tax heavily and build large bureaucracies.
A New Political Landscape After 1648
Following the Peace of Westphalia (1648), Europe shifted from religious wars to a system built around the balance of power. Conflicts were no longer driven mainly by religious divisions. Instead, diplomacy focused on preventing any one state from becoming too strong.
The logic was direct: if power stayed balanced, peace was more likely to hold.
This pushed states to form temporary alliances, even across religious lines, to check the ambitions of rivals. Powers like France, Austria, and England increasingly acted to preserve this equilibrium rather than to enforce religious uniformity.
France Under Louis XIV: Disrupting the Balance
France came out of the Thirty Years' War as Europe's strongest state. Under Louis XIV, the "Sun King," France tried to expand its borders and influence, which alarmed other powers. His nearly continuous wars are a key example of how dynastic and state interests provoked coalitions against him.
The Dutch War (1672 to 1678)
Louis invaded to seize territory, but his ambitions worried neighboring powers. Pressure from other states and Spain's entry into the fight pushed back against France. Though France made territorial gains, the war showed how Louis's aggression could rally his enemies into opposition.
The Nine Years' War (1688 to 1697)
In response to France's growing power, William of Orange helped organize a coalition that included England, the Holy Roman Empire, and Spain. This conflict, also called the War of the League of Augsburg, aimed to halt French expansion. France held on to some territory but was forced to recognize William as King of England, which hurt Louis's prestige.
The War of the Spanish Succession (1701 to 1713)
The biggest test of the balance of power came when Charles II of Spain died without an heir. His will left the throne to Philip of Anjou, Louis XIV's grandson, raising fears that France and Spain would unite under one crown. A coalition mobilized again to prevent this. The long, costly war ended with the Treaty of Utrecht (1713), which let Philip keep the Spanish throne but barred the union of the French and Spanish crowns.
The settlement also redrew Europe's map. As an example of the outcomes:
- Austria gained the Spanish Netherlands, Naples, Milan, and Sardinia.
- Britain gained Gibraltar and strengthened its position as a naval power.
- The Duke of Brandenburg was recognized as King of Prussia, a sign of Prussia's rising power.
- France was left deeply in debt, and Louis XIV's image suffered as public dissatisfaction grew.
Declining Powers: Poland, the Holy Roman Empire, and the Ottomans
As new powers rose, others weakened, often because they failed to centralize authority.
Poland: A Weak Monarchy
Poland's decline was rooted in its political system. The Polish king was elected by a parliament shaped by nobles, and key decisions required broad agreement, which made the state hard to govern. This lack of central authority left Poland open to foreign interference. The Polish monarchy could not consolidate power over the nobility, and by the late 18th century the country was partitioned by Russia, Prussia, and Austria until it disappeared from the map in 1795.
Holy Roman Empire: Fragmentation After Westphalia
The Holy Roman Empire, weakened by the Reformation and the Thirty Years' War, became little more than a collection of many semi-independent states. The emperor had little real authority, army, or revenue. Within the Empire, two German states gained prominence:
- Austria, under the Habsburgs
- Prussia, under the Hohenzollerns
These two powers would compete for influence in German affairs and shape the future of Central Europe.
Ottoman Empire: The End of Expansion
The Ottomans had long threatened Central Europe, but their defeat at the Battle of Vienna (1683) marked the end of their westward advance. A coalition led by Polish King Jan Sobieski repelled the Ottomans and began pushing them out of the region.
Austria kept fighting the Ottomans into the 18th century and reclaimed much of Hungary and the Balkans. The Ottoman Empire survived into the 20th century, but it entered a long period of stagnation and internal decline, later nicknamed "the sick man of Europe."
Military Advancements and the Rise of Modern Armies
New technology and strategies reshaped warfare in this era. Governments poured money into their militaries, which fed the military revolution.
⭐ Military Revolution: A shift toward greater reliance on infantry, firearms, mobile cannon, and more elaborate fortifications. These changes were financed by heavier taxation and required a larger bureaucracy, so states that could marshal enough resources gained an advantage in the new competitive system.
Sweden: Gustavus Adolphus and the Rise of Firepower
Under Gustavus Adolphus, Sweden became a military power that benefited from the military revolution. He pushed the use of mobile artillery, flexible tactics, and professional soldiers. These reforms let Sweden punch above its weight during the Thirty Years' War.
Spain: The Tercio and Habsburg Power
Spain under the Habsburgs also benefited from the military revolution, with a strong navy and the tercio infantry formation that combined pikemen and firearms. But constant warfare and heavy reliance on American silver drained Spanish resources. By the late 17th century, Spain had fallen behind other powers in military innovation and lost its leading position in Europe.
Competition and Coalition in a New Europe
The balance of power after Westphalia shaped European politics for a long time. States aligned based on interests, not religion. Some, like France, sought greater influence, while others formed coalitions to contain them.
This era saw fragmented or decentralized states like Poland and the Holy Roman Empire weaken, while states that centralized authority, including Austria and Prussia, grew stronger. Military reforms, economic resources, and effective governance became the deciding factors in a state's place on the European stage.
How to Use This on the AP European History Exam
Causation
Be ready to explain why states aligned and went to war after 1648. The strongest answers connect the balance of power to specific causes: dynastic claims (the Spanish succession), state expansion (Louis XIV's wars), and fear of one power growing too strong. Use the coalitions against France as a clear cause-and-effect chain.
Continuity and Change
Show the shift from religion-driven conflict before 1648 to interest-driven diplomacy after it. Note what continued too: war stayed common, and dynastic interests still mattered. This balance of change and continuity is exactly what these prompts reward.
Using Sources Effectively
On multiple-choice and document questions, treaties and war accounts often appear. Use the balance of power as a lens to read a source's purpose, such as why states wanted to block a French and Spanish union or partition Poland.
Common Trap
Don't reduce the era to "France versus everyone." The key idea is the system: shifting coalitions formed to prevent any one state from gaining too much control, and the makeup of those coalitions changed with circumstances.
Common Misconceptions
- Balance of power did not mean equal power for all states. It meant blocking any single state from becoming strong enough to control the continent.
- Westphalia did not instantly end all religious conflict, but it marked the point where religion stopped being the main driver of war between states.
- The military revolution was not just about better weapons. It tied military success to taxation, bureaucracy, and a state's ability to fund large armies.
- Poland's fall was not due to a lack of land or people. It came from a weak monarchy that could not consolidate authority over the nobility.
- The Holy Roman Emperor did not control a unified Germany. The Empire was a patchwork of many semi-independent states with little central power.
Related AP European History Guides
Vocabulary
The following words are mentioned explicitly in the College Board Course and Exam Description for this topic.Term | Definition |
|---|---|
balance of power | A principle of international relations in which no single state or coalition becomes dominant enough to threaten the independence of others, maintained through strategic alliances and territorial arrangements. |
Battle of Vienna | The 1683 military victory by Austria over the Ottoman Turks that halted Ottoman westward expansion into Europe. |
bureaucracy | Administrative systems and institutions developed by states to organize and manage military forces and resources. |
coalition | An alliance of multiple European powers formed to oppose a dominant state, such as the coalition against Louis XIV. |
competitive state system | The system of independent European states competing for power and influence, which led to new patterns of diplomacy and warfare after 1648. |
diplomacy | The practice of negotiation and communication between states to manage international relations and resolve conflicts. |
dynastic interests | The political and territorial goals pursued by ruling families to expand their power and secure their dynasty's succession and wealth. |
firearms | Weapons using gunpowder that gradually replaced traditional medieval weapons like bows and crossbows. |
fortifications | Defensive structures and military installations designed to protect territory and resist siege warfare. |
infantry | Soldiers who fight on foot, which became increasingly important in military strategy during this period. |
Louis XIV's wars | The nearly continuous military conflicts pursued by Louis XIV of France to advance both dynastic and state interests, provoking opposition from other European powers. |
military revolution | A transformation in military technology, tactics, and organization that fundamentally changed warfare and required states to develop new institutions and resources. |
military technology | Weapons, equipment, and innovations used in warfare, such as machine guns, poison gas, tanks, and aircraft that fundamentally changed combat tactics in World War I. |
mobile cannon | Portable artillery pieces that could be moved across battlefields, increasing the effectiveness of military forces. |
Peace of Westphalia | A series of treaties signed in 1648 that ended the Thirty Years' War and established the principle of state sovereignty in Europe. |
Poland's partition | The division of Polish territory among Prussia, Russia, and Austria in the late 18th century, resulting from the Polish monarchy's inability to consolidate authority. |
state interests | The political, economic, and military objectives pursued by a nation-state to increase its power and security. |
taxation | Revenue collection by states used to finance the increased costs of military technology and larger armies. |
warfare | Military conflict and combat strategies that evolved with new technologies and techniques during this period. |
Frequently Asked Questions
What is balance of power in AP European History?
Balance of power is the idea that European states tried to prevent any one state from becoming strong enough to control the others.
How did the Peace of Westphalia change European diplomacy?
After 1648, European diplomacy shifted away from mainly religious conflict and toward state interests, sovereignty, alliances, and preventing one power from gaining too much influence.
Why did Louis XIV disrupt the balance of power?
Louis XIV expanded French power through repeated wars, which alarmed other European states and pushed them to form coalitions against France.
Why was the War of the Spanish Succession important?
It tested whether France and Spain would unite under one Bourbon line. The Treaty of Utrecht prevented that union and preserved the balance of power.
How did the military revolution affect balance of power?
The military revolution favored states that could tax more effectively, build bureaucracies, maintain professional armies, and afford new weapons and fortifications.
How should I use balance of power on the AP Euro exam?
Use it as evidence for causation and continuity/change: why alliances shifted after 1648, why states opposed French expansion, and how warfare became tied to state-building.