Border history
How did Prussia become Germany? The rise of Prussia and the unification of the German states
The creation of Germany in 1871 was one of the most important political transformations in nineteenth-century Europe. For centuries, the German-speaking lands had been divided among numerous kingdoms, duchies, principalities and independent cities, with no single government exercising authority over the entire German population. The state that eventually united most of these territories was Prussia, a kingdom whose origins lay partly outside the traditional geographical center of Germany. During the eighteenth and nineteenth centuries, Prussia developed into a major European military power, challenged Austria for leadership of the German states and eventually used diplomacy, economic influence and a series of wars to create the German Empire. Yet describing this process as Prussia simply becoming Germany is not entirely accurate. Prussia did not disappear in 1871, nor did the other German states become ordinary Prussian provinces. Instead, they entered a new federal empire dominated by the Prussian monarchy, army and political institutions. The Kingdom of Prussia remained the largest constituent state of Germany until the overthrow of the monarchy in 1918, while Prussia itself survived as a republican state until its formal abolition after the Second World War. Understanding how Prussia became the foundation of modern Germany therefore requires examining the rise of the Hohenzollern dynasty, the competition between Prussia and Austria, the development of German nationalism and the political strategy of Otto von Bismarck.

Brandenburg, Prussia and the Origins of the Hohenzollern State
The origins of Prussia were considerably more complicated than those of a typical European kingdom. The territory that eventually became the Prussian state developed from two geographically separate political entities: Brandenburg, situated in northeastern Germany, and Prussia, located along the southeastern coast of the Baltic Sea.
Brandenburg formed part of the Holy Roman Empire, the loose political structure that governed much of Central Europe during the Middle Ages. In 1415, the Hohenzollern dynasty acquired the electoral dignity associated with Brandenburg, giving the family an important position within imperial politics. The rulers of Brandenburg were among the prince-electors entitled to participate in choosing the Holy Roman Emperor, although their territorial possessions remained relatively modest compared with those of some other German princes.
Prussia had a different history. During the thirteenth century, the Teutonic Order established a crusading state along the Baltic coast after conquering territories inhabited by the Old Prussians, a Baltic-speaking population distinct from the later German-speaking inhabitants of Prussia. The Order subsequently lost much of its power through conflict with Poland and Lithuania.
In 1525, the grand master of the Teutonic Order, Albert of Hohenzollern, secularized the remaining territory under his control and established the Duchy of Prussia. The duchy became a hereditary possession of the Hohenzollern family under the suzerainty of the Polish crown.
A decisive dynastic change occurred in 1618, when the Brandenburg branch of the Hohenzollern family inherited the Duchy of Prussia. The two territories were joined under a common ruler, creating the political formation commonly known as Brandenburg-Prussia.
This state was geographically fragmented. Brandenburg lay within the Holy Roman Empire, while the Duchy of Prussia was situated farther east and outside the empire's boundaries. The Hohenzollerns also controlled scattered territories elsewhere in Germany.
The new political entity therefore lacked the territorial unity that later generations would associate with a nation-state. Its rulers governed separate lands with different historical institutions, legal traditions and political relationships.
However, the combination of Brandenburg and Prussia gave the Hohenzollerns an important advantage. Their territories extended across strategically significant parts of northern and eastern Central Europe, while their dynastic position allowed them to participate in both imperial German politics and the wider struggle for influence around the Baltic Sea.
During the seventeenth century, Frederick William, known as the Great Elector, strengthened the state's central administration and developed a standing army. He also secured full sovereignty over the Duchy of Prussia through agreements with Poland during the 1650s, confirmed internationally in 1660.
These developments created the institutional foundations of the future Prussian kingdom. The Hohenzollerns increasingly built a centralized military and administrative state capable of exercising authority over their widely separated territories.
How Prussia Became a European Great Power
Prussia's transformation into a kingdom occurred in 1701. Frederick III, the Elector of Brandenburg, obtained imperial recognition for his assumption of the royal title and crowned himself Frederick I, King in Prussia.
The wording was significant. Brandenburg still belonged to the Holy Roman Empire, where the Habsburg ruler possessed the imperial title. The Duchy of Prussia, however, lay outside the empire, allowing the Hohenzollerns to claim a royal dignity without directly challenging the imperial constitutional order.
Over time, the name Prussia became increasingly associated with the entire Hohenzollern state, even though Brandenburg remained one of its most important political and demographic centers. Berlin, located in Brandenburg, developed into the monarchy's capital.
During the eighteenth century, successive Prussian rulers strengthened the army, bureaucracy and financial administration. Frederick William I, who ruled from 1713 to 1740, became particularly associated with military organization and administrative discipline. Under his government, Prussia maintained an army unusually large in relation to its population.
The reign of Frederick II, commonly known as Frederick the Great, transformed Prussia into a major European power. Shortly after taking the throne in 1740, he invaded Silesia, a wealthy Habsburg territory with important economic resources. The resulting wars established Prussian control over most of Silesia and intensified the rivalry between Prussia and Austria.
The Seven Years' War of 1756–1763 further demonstrated Prussia's military significance. Frederick fought against a coalition that included Austria, France and Russia. Although Prussia came close to defeat, it survived the conflict and retained Silesia, confirming its status as one of Europe's leading powers.
Prussia also participated in the partitions of the Polish-Lithuanian Commonwealth during the late eighteenth century. These territorial acquisitions connected previously separated Prussian possessions and expanded Hohenzollern rule over substantial Polish-speaking populations.
By the end of the century, Prussia had become a powerful multinational monarchy. Its subjects included German speakers, Poles, Lithuanians and other communities, while its territory extended beyond the boundaries of the historical German political world.
This distinction would later become important. Prussia was not simply a German national state waiting to unite other Germans. It was a dynastic kingdom whose rulers sought military strength, territorial security and European influence. German unification would eventually become a means of achieving these objectives, but it was not the original purpose of Prussian state-building.
Napoleon and the Emergence of German Nationalism
The French Revolution and the Napoleonic Wars fundamentally changed the political environment in which Prussia operated. The Holy Roman Empire, already weakened by centuries of political fragmentation, could not withstand the expansion of French power.
In 1806, Napoleon reorganized numerous German territories into the Confederation of the Rhine, placing them under French influence. Emperor Francis II subsequently dissolved the Holy Roman Empire, bringing an end to an institution that had existed for roughly a millennium.
Prussia attempted to resist French domination but suffered a devastating defeat at the battles of Jena and Auerstedt in October 1806. Napoleon's forces occupied Berlin, and the Treaty of Tilsit in 1807 forced Prussia to surrender extensive territories and accept severe restrictions.
The defeat exposed serious weaknesses in Prussia's political and military institutions. In response, reformers such as Heinrich Friedrich Karl vom und zum Stein, Karl August von Hardenberg, Gerhard von Scharnhorst and August Neidhardt von Gneisenau introduced important changes to administration, society and the armed forces.
The reforms included measures affecting serfdom, municipal government, military recruitment and opportunities for advancement within the army. Although their results were uneven and did not create a democratic state, they helped modernize Prussian institutions.
Napoleon's domination also encouraged the development of German nationalism. Intellectuals and political activists increasingly argued that German-speaking peoples possessed a common historical and cultural identity that should find political expression.
Before this period, many inhabitants of the German lands had primarily identified with particular cities, principalities or dynasties. The experience of French occupation helped popularize the idea that the German territories might form a larger political community.
Prussia became an important center of resistance during the final years of the Napoleonic Wars. In 1813, it joined the coalition fighting France and contributed significantly to Napoleon's defeat. Prussian forces later participated in the Battle of Waterloo in 1815 under Field Marshal Gebhard Leberecht von Blücher.
The Congress of Vienna rewarded Prussia with substantial territorial acquisitions, including important parts of the Rhineland and Westphalia in western Germany.
These western territories would have enormous long-term consequences. They contained growing industrial regions, coal deposits and urban centers that became essential to Prussia's economic development during the nineteenth century.
The Napoleonic period therefore transformed Prussia in two ways. Military defeat encouraged institutional reform, while the postwar settlement gave it territories that strengthened its position within the German-speaking world.
At the same time, the idea of a unified Germany became increasingly influential, creating a political movement that Prussia would eventually seek to control.
Prussia, Austria and the Struggle for German Leadership
After Napoleon's defeat, the Congress of Vienna established the German Confederation in 1815. It consisted of thirty-nine states, including Prussia, Austria, Bavaria, Saxony, Württemberg and numerous smaller principalities and free cities.
The German Confederation was not a unified country. It possessed a federal assembly based in Frankfurt, but its member states retained their own governments, armies and most important domestic institutions.
Austria initially occupied the leading position within the confederation. The Habsburg monarchy had historically dominated the Holy Roman Empire, and Austrian statesmen sought to preserve their influence over Central Europe.
Prussia, however, increasingly challenged this position. Its territories extended across northern Germany, and its economic and military strength continued to grow.
The rivalry between Austria and Prussia reflected two competing visions of Germany.
One possibility was a Greater German solution, which would include Austria or its German-speaking lands within a broader German state. This approach faced major difficulties because the Habsburg monarchy also ruled extensive territories inhabited by Hungarians, Czechs, Croats, Italians and other nationalities.
The alternative was a Lesser German solution, which would establish a unified Germany without Austria, allowing Prussia to become the dominant power.
Economic developments increasingly favored Prussia. In 1834, a customs union known as the Zollverein came into operation under Prussian leadership. It removed many internal trade barriers among participating German states and encouraged commercial integration.
Austria remained outside the union, weakening its ability to direct the economic development of the other German territories.
The Zollverein did not itself create German political unity, but it demonstrated the practical advantages of cooperation under Prussian leadership. Railway construction, industrial expansion and the growth of commercial networks strengthened the connections among participating states.
Political nationalism also became more influential. During the revolutions of 1848, representatives from across the German states gathered in Frankfurt to draft a constitution for a unified Germany.
The Frankfurt Parliament attempted to establish a constitutional monarchy with representative institutions. In 1849, it offered the imperial crown to Frederick William IV of Prussia.
The king refused. He was unwilling to accept an imperial title offered by a revolutionary national assembly without the agreement of Germany's established rulers. The failure of the Frankfurt Parliament demonstrated that liberal nationalism lacked the military and political power necessary to impose unification.
Nevertheless, the events of 1848 established a crucial precedent. The idea of German unity had become a central political question, and Prussia had emerged as the most important possible leader of a Germany that excluded Austria.
The issue was no longer simply whether the German states might unite, but which power would determine the conditions of their unification.
Bismarck and the Wars That Transformed Germany
The decisive phase of German unification began after Otto von Bismarck became Prussia's minister-president in 1862. Appointed by King William I, Bismarck sought to strengthen the monarchy and overcome parliamentary opposition to military reform.
Bismarck was not primarily a liberal nationalist. He was a conservative statesman committed to preserving royal authority and expanding Prussian power. Nevertheless, he recognized that the movement for German unity could be used to achieve Prussia's strategic objectives.
His policy combined diplomatic calculation with a willingness to employ military force. Rather than attempting to unite Germany through parliamentary negotiation alone, Bismarck sought to change the balance of power among the German states.
The first major conflict occurred in 1864, when Prussia and Austria fought Denmark over the duchies of Schleswig and Holstein. The dispute involved complicated dynastic, legal and national claims, particularly concerning territories with both German- and Danish-speaking populations.
Prussia and Austria defeated Denmark, and the resulting settlement placed Schleswig and Holstein under their joint control. However, the arrangement also created new disagreements between the two victorious powers.
Bismarck exploited these tensions to prepare a confrontation with Austria. In 1866, war broke out between Prussia and Austria, with several German states supporting each side.
The conflict, often called the Austro-Prussian War or Seven Weeks' War, ended in a decisive Prussian victory. At the Battle of Königgrätz, also known as Sadowa, Prussian forces defeated the principal Austrian army in July 1866.
The military result fundamentally transformed German politics. Austria was excluded from the future organization of Germany, and the German Confederation was dissolved.
Prussia annexed several territories, including Hanover, Hesse-Kassel, Nassau, Frankfurt and the duchies of Schleswig and Holstein. These acquisitions gave Prussia greater territorial continuity across northern Germany and eliminated several governments that had opposed it.
In 1867, Prussia organized the North German Confederation, bringing together the German states north of the Main River under a federal constitution.
The new confederation possessed common political and military institutions and was dominated by Prussia. William I served as its federal president in his capacity as king of Prussia, while Bismarck became its chancellor.
The southern German states, including Bavaria, Württemberg and Baden, remained outside the confederation. However, they established military alliances with Prussia, preparing the foundation for eventual political integration.
Bismarck had therefore achieved a major part of German unification without creating a fully unified German Empire. Austria had been removed from German leadership, northern Germany was politically organized under Prussian dominance, and the remaining southern states were increasingly dependent on Prussian military power.
The final stage would emerge from a war with France.
The Franco-Prussian War and the Proclamation of the German Empire
French leaders viewed the growing power of Prussia with concern. The defeat of Austria in 1866 had dramatically altered the European balance of power, and the creation of the North German Confederation made Prussia the dominant force in northern Germany.
The immediate crisis developed in 1870 over the proposed candidacy of a Hohenzollern prince for the Spanish throne. France feared that the accession of a member of the Prussian royal family in Spain would create a strategically unfavorable situation.
Although the candidacy was withdrawn, French officials demanded further guarantees from King William I. Bismarck edited and published a report of the king's encounter with the French ambassador, producing the famous Ems Dispatch. Its presentation intensified public anger and diplomatic tensions.
France declared war on Prussia in July 1870.
Bismarck's diplomatic position was favorable because the southern German states joined Prussia under their existing military agreements. The war therefore brought together forces from both northern and southern Germany against a common external opponent.
German armies achieved rapid victories. In September 1870, French Emperor Napoleon III was captured at the Battle of Sedan, causing the collapse of the Second French Empire. The conflict nevertheless continued as the newly proclaimed French republic attempted to resist the German invasion.
The war strengthened support for political unification among German rulers. Negotiations between the North German Confederation and the southern states produced agreements allowing the latter to enter an enlarged federal state.
On 18 January 1871, the German Empire was proclaimed in the Hall of Mirrors at the Palace of Versailles, outside Paris.
William I, the king of Prussia, became German Emperor. Bismarck became the first imperial chancellor.
The location of the proclamation was symbolically important. The new empire was announced in the palace associated with the French monarchy while German armies were still fighting France.
The war ended with the Treaty of Frankfurt in May 1871. France was required to pay a large indemnity and surrender most of Alsace and part of Lorraine to the German Empire.
The annexation contributed to long-term hostility between France and Germany. It also demonstrated that the new German state had emerged through military victory and territorial expansion rather than solely through peaceful national agreement.
The German Empire of 1871 did not include Austria, even though millions of German speakers lived within the Habsburg monarchy. Nor did it unite every German-speaking community in Europe.
Instead, it represented the Lesser German solution: a federal German state created under Prussian leadership and excluding Austria.
The proclamation of 1871 therefore marked the success of Prussia's struggle for German leadership, but it did not mean that Prussia had simply changed its name.

Why the German Empire Was Dominated by Prussia
The German Empire established in 1871 was formally a federation of kingdoms, grand duchies, duchies, principalities and free cities. Bavaria, Saxony and Württemberg retained their monarchies, while other member states preserved important political institutions.
Prussia remained one of these constituent states, but its position was overwhelmingly dominant.
It occupied approximately two-thirds of the empire's territory and contained about three-fifths of its population. Berlin served as the imperial capital, and the king of Prussia simultaneously held the office of German Emperor.
The imperial constitution created a federal legislature consisting of the Reichstag and the Bundesrat. The Reichstag was elected through universal male suffrage, while the Bundesrat represented the governments of the constituent states.
Prussia possessed enough votes in the Bundesrat to block constitutional amendments, giving it exceptional influence over the structure of the empire.
The imperial chancellor was appointed by the emperor rather than being responsible to a parliamentary majority in the modern democratic sense. Bismarck also served as Prussian minister-president for much of his chancellorship, concentrating important federal and Prussian responsibilities in the same political leadership.
Military institutions reflected Prussian predominance as well. Although some states retained particular administrative traditions and military privileges, the Prussian army provided the principal organizational model for the imperial armed forces.
The German Empire was therefore neither a centralized unitary state nor an equal partnership among its constituent members. It was a federation whose institutions preserved significant regional autonomy while giving Prussia disproportionate political and military power.
This arrangement also explains why Germany did not develop through the straightforward expansion of Prussian provincial administration. Bavaria remained Bavaria, Saxony remained Saxony, and Württemberg retained its own royal dynasty.
At the same time, the empire included populations whose national identities did not correspond neatly to the idea of a unified German nation. Prussia's eastern territories contained substantial Polish-speaking communities, while other parts of the empire included Danes, French speakers and additional minorities.
German unification therefore did not create an ethnically uniform state. It brought together existing political territories under a common imperial framework, preserving many of their internal differences while reinforcing Prussian authority.
The result was a powerful new European state. Its industrial economy expanded rapidly, particularly in the Ruhr and other manufacturing regions, while its military strength altered the balance of power on the continent.
Germany had been unified, but the political structure of that Germany reflected the institutions, strategic objectives and conservative monarchy of Prussia.
How Prussia Disappeared but Germany Survived
The German Empire established in 1871 lasted until the end of the First World War. Germany's defeat in 1918 led to revolutionary unrest, the abdication of Emperor William II and the collapse of the Hohenzollern monarchy.
The fall of the imperial system also ended the Prussian kingdom. However, Prussia did not immediately disappear as a political entity.
Under the Weimar Republic, Germany remained a federal state, and Prussia became the Free State of Prussia. It was still the largest German constituent state and contained a substantial majority of the country's population.
The Treaty of Versailles of 1919 reduced Germany's territory and significantly affected Prussia's former provinces. West Prussia and Posen were largely transferred to the restored Polish state, while other border regions were divided through treaties and plebiscites. East Prussia became geographically separated from the remainder of Germany by Polish territory.
These changes weakened Prussia's historical territorial structure but did not eliminate it.
During the Weimar period, Prussia developed its own republican institutions and was governed for much of the period by a coalition led by the Social Democratic Party. Its political character differed considerably from the militarized conservative monarchy associated with the nineteenth century.
The rise of National Socialism eventually destroyed this federal autonomy. In 1932, the German national government removed Prussia's elected government in the event known as the Preußenschlag, or Prussian coup. After Adolf Hitler came to power in 1933, the Nazi dictatorship systematically dismantled the constitutional independence of Germany's states.
By the middle of the 1930s, Prussia had largely lost its meaningful autonomous political institutions, although it continued to exist formally.
The final destruction of the Prussian state occurred after the Second World War. Germany's defeat in 1945 brought Allied occupation, the loss of territories east of the Oder–Neisse line and the displacement or expulsion of millions of Germans from areas that had historically belonged to Prussia.
Much of East Prussia was divided between Poland and the Soviet Union, while other former Prussian territories were transferred to Poland or reorganized within occupied Germany.
On 25 February 1947, the Allied Control Council formally abolished the State of Prussia through Control Council Law No. 46. The law characterized Prussia as a historical center of German militarism and reaction and declared that the Prussian state, its central government and its agencies were abolished.
The decision did not abolish Germany. Instead, the former Prussian territories remaining within Germany were reorganized into new states or incorporated into existing ones.
When the Federal Republic of Germany was established in 1949, it inherited many territories that had once belonged to Prussia, including regions of North Rhine-Westphalia, Lower Saxony, Hesse and Schleswig-Holstein. East Germany, also established in 1949, included other former Prussian territories, although its internal states were later replaced by administrative districts.
German reunification in 1990 restored a single German state but did not restore Prussia as a political entity.
The historical relationship between Prussia and Germany therefore has a paradoxical outcome. Prussia created the political framework through which most of the German states were united in 1871, yet the Prussian state itself eventually disappeared while Germany survived.
The reasons for Prussia's success lay in the gradual accumulation of military, economic and institutional power. Its rulers transformed a collection of scattered territories into a major European kingdom, acquired valuable industrial regions and challenged Austria for leadership of the German-speaking world. During the nineteenth century, the Zollverein strengthened Prussian economic influence, while Bismarck's wars established the political conditions for unification.
But the German Empire was never simply Prussia under another name. It was a federal state created through the incorporation of other German monarchies and territories, with Prussia occupying the dominant position within that structure.
The modern German state is therefore the historical successor of a unification process led by Prussia, not the continuation of Prussia as a separate kingdom. The distinction explains why Germany remains a federal country, why Berlin became its capital and why Prussian institutions exerted such a profound influence on German political history.
Prussia did not literally become Germany. It provided the monarchy, military strength and political leadership through which a new German state was created. Its greatest historical achievement was also the beginning of a transformation that eventually made Prussia itself unnecessary as a separate political entity.