"Germany will be united not by words, but by blood and iron."

Bismarck the Triumphant. A cartoon from Punch magazine.
German question
The central issue in Germany from the mid-18th century and into the 19th century was unification. Historically, Germany had been fragmented into dozens of state entities, kingdoms, duchies, principalities, and free cities. The two largest powers—the Austrian Empire and Prussia—claimed hegemony in Germany.
During this period, there was no single German people (Deutsche), nor was there a single German language. Prussians, Saxons, Silesians, Bavarians, Hessians, Alsatians, and other Germans spoke different languages, often completely incomprehensible to one another.
Until 1806, Germany was dominated by the Habsburg Empire, its monarch serving as Emperor of the Holy Roman Empire of the German Nation, a supranational union that had existed since 962. However, Napoleon Bonaparte defeated the Austrian Empire, significantly undermining its influence in Italy and Germany. The great Frenchman also abolished the Holy Roman Empire, creating the Confederation of the Rhine, headed by the Emperor of France.
The Confederation of the Rhine was dissolved in 1813, following Bonaparte's defeat at Leipzig. In 1815, the German Confederation was formed, dominated by Austria and Prussia, the two most powerful German powers. However, while Prussia's role steadily grew, Austria's position weakened.
Accordingly, two concepts of German unification existed in Germany. The first was the Lesser German path, a unification of the German lands and peoples around the Kingdom of Prussia, excluding Austria, which included the lands of Bohemia, Slovakia, Poland, Slovenia, Hungary, Dalmatia, Croatia, parts of Italy, and so on.
The second was the Greater German idea, a unification of Germany under Austria and the Habsburg dynasty. This concept had many supporters among the smaller German states, which feared absorption into the Kingdom of Prussia. Within the Austrian Empire, the electoral princes would have retained considerable autonomy.
Prussia, which, after the defeat of Napoleon's empire, had nearly doubled its territory by acquiring the Duchy of Poland, the Rhineland, and northern Saxony, and possessed a developed industrial potential, gradually pushed aside its competitors. In 1834, the German Customs Union was founded, abolishing internal customs duties. Monetary unification began. Prussia played a leading role in the union.

The first attempts at German unification: from below and from above
In 1848–1849, a revolutionary wave swept through Germany, demonstrating the growing role of the bourgeoisie. The new bourgeois class, the city dwellers, demanded German unification "from below," which contributed to the collapse of the old feudal order and the region's economic development. The German National Assembly (Frankfurt Parliament) convened in Frankfurt am Main, adopting the Imperial Constitution and transferring the crown to the Prussian King Friedrich Wilhelm.
Many German states recognized the imperial constitution. However, the largest states, led by Austria and Prussia, refused to recognize it, unwilling to support German unification "from below." The reactionary monarchies suppressed the revolutionary and patriotic movement. The Frankfurt Parliament was dispersed.
The Prussian King Friedrich Wilhelm, who had refused the imperial crown offered to him by delegates to the Frankfurt Parliament, established the Erfurt Confederation in May 1849. The union was created with the aim of suppressing the revolution, "establishing a unified leadership of German affairs," and creating a single federal state (the German Reich) under the supremacy of the House of Hohenzollern (the kings of Prussia). A draft constitution was prepared. Most of the German states joined this union.
Naturally, Vienna opposed this union. Saxony and Hanover withdrew. The Erfurt Parliament was never established. At the initiative of the Austrians, the Diet of the German Confederation (the Frankfurt Diet) was convened, which was intended to restore the previous order in Germany. Berlin refused to recognize this Diet.
Matters were complicated by the conflict in Hesse and the sluggish Danish-German War of 1848–1850 (the First Schleswig War), in which the German states and Denmark divided the duchies of Schleswig and Holstein. The war ended, under pressure from England and Russia (Denmark's allies), with a return to the status quo on the Schleswig-Holstein issue.
Austro-Bavarian troops, by decision of the Diet, were to suppress revolutionary unrest in the Principality of Hesse. But the roads connecting Prussia with its possessions in western Germany ran through Hesse. The Prussians had no intention of allowing the Bavarians to pass.
This led to military clashes. The situation escalated toward a military confrontation between Prussia and Austria – the so-called "Autumn Crisis" of 1850. Under pressure from Russia and Austria, Prussia was forced to yield. By the Treaty of Olmütz, Prussia renounced its claims to leadership in Germany and its attempts to resolve the Schleswig-Holstein issue in its favor. The German Confederation was restored. Within Prussia, the treaty was perceived as the "disgrace of Olmütz," and the course toward German unification remained.

At the Berlin barricades in March 1848
Improving the foreign policy situation for Prussia
Several events subsequently occurred that weakened the influence of external players on German affairs. First, the Crimean War resulted in the defeat of the Russian Empire, which since the defeat of Napoleon had been the "gendarme of Europe" and had sought to uphold the principle of legitimacy, preserve the old order, and preserve monarchies.
Russia was also a long-standing ally of Austria and supported it. After the Crimean War, when Vienna, under pressure from Paris and London, was about to turn against Russia, relations between Russia and Austria deteriorated significantly. St. Petersburg abandoned the vicious practice of supporting Austria at the expense of national interests.
On the contrary, Russia's relations with Prussia improved. Otto von Bismarck, who served as Prussian ambassador to Russia from 1859 to 1862, facilitated this process. Wilhelm ascended the throne in Prussia (regent from 1858, when King Friedrich Wilhelm became incapacitated due to illness, and king from 1861), and he strove to maintain friendly relations with Russia.
During the Polish Uprising of 1863, when a new Crimean War threatened, Prussia was the only power to support Russia and help suppress the uprising in Poland. As a result, Russia favorably viewed the unification of Germany "by blood and iron" under Prussian leadership.
Austria was losing ground in Germany. It had lost Russia's friendly support and was distracted by affairs in Italy, where it was also losing lands under pressure from Sardinia (the kingdom had led the process of Italian unification "from above") and France. Furthermore, a significant portion of the Habsburg Empire's elite, especially the Hungarians, opposed the expansion of the empire into Germany. This significantly increased the proportion of the German population, undermining Hungarian interests.
France, which could have prevented German unification, was weakened by the foreign policy adventures of Napoleon III's government, particularly the failed expedition to Mexico. The struggle over colonial redistribution between France and Britain continued. The French and British clashed in Latin America, Africa, and Asia.
France could not support Austria, as it supported the unification of Italy (which was hampered by the Habsburg Empire), hoping to draw Italy into its sphere of influence. Thus, during the Austro-Italian-French War of 1859, the Austrian Empire was defeated. Lombardy and Central Italy were incorporated into Sardinia; Sardinia ceded Savoy and Nice to France. In 1860, Austria planned to take revenge, but Russia forced Vienna to abandon these plans.
England, which pursued a traditional "divide, pit, and rule" policy in continental Europe, generally had no intention of interfering in the process of German unification. Moreover, Prussia was seen as a counterweight to France, with which England was engaged in a number of conflicts at the time, particularly in the colonies. The British disliked the French attempting to subjugate Mexico, annex Belgium, and the French Suez Canal project, which threatened British dominance in India. Initially, the British opposed the French-led Suez Canal project. Only after Prussia defeated France in 1870 did the British seize control of the canal.
Prussia didn't see a threat, as Berlin had previously been London's ally in the struggle against France and Russia (the Seven Years' War). The new Germany, with its Prussian core, could contain France, Russia, and Austria. Britain also viewed Germany as a promising market for English goods.
Mad Bismarck
The personification of Prussia's policy of unifying Germany was the head of the government and Minister of Foreign Affairs of Prussia, Otto von Bismarck, nicknamed by his contemporaries "Mad Bismarck."
Bismarck understood perfectly well that the unification of Germany would be hindered by other European powers. The emergence of a new powerful state in the center of Europe was unfavorable for them. Together, they could easily thwart the Kingdom of Prussia. This meant that Prussia would have to resolve the issue with Russia and France at the very least. The "Iron Chancellor" also understood this well, as he also understood. No diplomacy would help in this matter. Vienna would hinder Berlin to the last. The German question would ultimately be resolved by force. "Not by words, but by blood and iron will Germany be united," Bismarck said.
Even before Bismarck assumed control of Prussia's foreign policy in 1862, he held three important posts, which allowed him to thoroughly study the policies of the major players in Europe. First, he served as Prussia's representative to the Frankfurt Parliament, where he thoroughly studied the situation of the German states and Austria. He opposed the anti-Russian policy of the Vienna Cabinet, which was attempting to mobilize the armies of the German states. Bismarck then served as ambassador to Russia, where he maintained close contacts with Vice-Chancellor Gorchakov and Russian Emperor Alexander II. After St. Petersburg, Bismarck served as ambassador to Paris, where he thoroughly explored the strengths and weaknesses of Bonapartism.
In Prussia, Bismarck became an indispensable assistant to King Wilhelm. In particular, Bismarck exercised complete control over the kingdom's foreign policy. As the king himself said, "I cannot, like you, with only two hands, throw and catch five balls at once." Wilhelm thus emphasized the minister's dexterity in political affairs.
Bismarck always knew how to seize an opportune moment, to "catch the bird of fortune by the tail." He took advantage of the Polish Uprising of 1863. The Polish question was extremely dangerous for Russia. England and France exerted diplomatic pressure on Russia, and rumors of a new Crimean War were circulating. Austria, as usual, hesitated, but leaned toward the French and English.
Prussia supported Russia in the fight against the Polish insurgents. Berlin refused to join the political position of England and France. Berlin also made it clear that it would not welcome the presence of Anglo-French forces in the Baltic.
St. Petersburg took a hard line on the Polish issue and refused to budge. Tsar Alexander II showed his resolve. France and England, which were not prepared to fight Russia at the time, were forced to give in. Moreover, the uprising itself had already been suppressed.

To be continued ...
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