Since the 17th century, Germany has been in a state of fragmented feudal separation. By the first half of the 19th century, Prussia had become the most powerful kingdom among the states, and Bismarck, when he became prime minister of Prussia, proposed to unify Germany through war.

The international situation at that time was very favorable for Bismarck to wage war. Russia was weakened in the Crimean War and has not yet recovered. Austria did not support Russia in this war, but instead concluded an alliance with Britain and France, which led to discord between Russia and Austria. France's power was relatively strong, and Britain was afraid that France would dominate Europe, so it supported Prussia and contained France.

France hoped that Prussia and Austria would go to war and prepare to reap the benefits, but Bismarck, after recognizing the situation, decided to use a series of tactics and diplomatic means to clear the external obstacles to the reunification of Germany.

Austria was one of the most powerful states in Germany, openly and covertly competing with Prussia for the leadership of unification. Bismarck used a plot to capture the old man and was the first to target Austria.

In 1863, Danish troops marched into the Duchy of Holstein and Schleswig, members of the German Confederation. Bismarck used this as an excuse to co-opt Austria to send troops together. After the war, Prussia occupied the Duchy of Schleswig, and Bismarck gave the Duchy of Holstein to Austria generously.

Bismarck's move had three intentions: First, the purpose of uniting Austria was to isolate Austria, and once Prussia switched to war against Austria, Denmark would certainly not come to Austria's aid. Second, in the Danpu War, Bismarck figured out the details of the Austrian army, thus laying the foundation for the victory over Austria. Thirdly, Holstein never belonged to Austria, nor did it share a border with Austria, but was nominally assigned to Austria, which in fact could hardly be effectively ruled by Austria.

Before waging the war against Austria, Bismarck fought for French neutrality in this war. For this reason, he adopted a diplomatic trick of throwing bricks and stones, repeatedly hinting to France that after the end of the war, Prussia would give France a certain amount of territory. After stabilizing France, Bismarck formed an alliance with Italy, Austria's enemy, and launched a brazen war against Austria in June 1866.

Because the Prussian army had been planning for a long time and was overwhelmed in the war, the Austrian army collapsed on all fronts. At this time, Bismarck clearly realized that the complete defeat of Austria was not the goal, but the ultimate goal was to achieve the unification of Germany. France, which had always opposed the unification of Germany, was Prussia's most dangerous enemy. If the war against Austria were to end in due course, Austria would be grateful to Dade and would at least remain neutral after the Franco-Prussian war. Bismarck persuaded his opponents to withdraw his troops to end the Austro-Prussian war.

Bismarck further isolated France diplomatically, cleverly altering the "Ames telegram", which angered France. On July 19, 1870, the Franco-Prussian War broke out. In the end, the war ended in a total defeat for France. Bismarck cleared the last obstacle on the road to reunification, and on January 18, 1871, he finally realized his dream of establishing a united Germany.

This system is "the calculation in the volt, the ring is connected", the comprehensive calculation, the optimal combination, can exert infinite power, not a certain strategy can achieve. When dealing with the world, the weaker side than oneself can use a chain strategy to expand the results of the battle; Compared with the side that is stronger than yourself, you can also turn defeat into victory by using a chain plan, which is the beauty of a chain plan.