As a Prussian, Bismarck is uncommonly loyal to his homeland and therefore, he would only allow the unification of Germany to happen with Prussia as the leader. War was necessary for unification because the balance of great powers would be imbalance as a result and so, Bismarck reformed the army till the point that he was known as Iron Chancellor. After years of revolutions in Europe, Bismarck turned up right in the middle of the commotion and used his Realpolitik's policies to raise Prussia's name. The feeling of nationalism had never eroded from the Prussians' heart and Bismarck used his influential and manipulative approach by taking this advantage.
Apparently, the dispute over Holstein and Schleswig was not solved and the Prusso-Danish war occurred. He took this great opportunity to test the fighting ability of Prussian army and also, this war served as the very first step taken by Bismarck to make Prussia's reputation well known all over the Europe's continent. The Austro-Prussian war followed soon and Prussia's main aim had finally achieved with the dissolvent of German Confederation, which the dominant country, Austria had always been Prussia's firm enemy due to the geographical and economic purposes. Consequently, this inevitable war would help Prussia to get rid of Austria once and for all. With Austria's defeat, Bismarck had showed who should has the right to rule over the German empire and the North German Confederation was established in the end.
Generally, France would not stood still to see a strong united Germany to be at her border. When the crown in Spain was vacant, it had literally opened another great spot for the other great powers to fill in the place. This means that the nation's territory become larger. The Ems telegram was a scheme that Bismarck played very well as it succeeded in arousing national anger in both France and Prussia. Bismarck knew that Prussia had to emerge above France in order to make herself the natural leader of a united Germany and also, for their hunger for power. The defeat of France functions as the last key to unify Germany, which was finally completed in 1971.
With three consecutive wars, Prussia's economic status had taken a financial hit. However, the establishment of Zollverein proved to be a great source to Prussia's economic growth. At the same time, Prussia managed to make herself the leader of the association, leaving Austria isolated. The industrialization and railway's creation contribute a lot to make her to become the leading country of a united Germany. Bismarck transformed Prussia's economy to a centralized economy, which would decrease the nation's investment on military.
In conclusion, the unification would not happen if the international tensions didn't appeared but the emergence of Bismarck had strengthened the German's union. Needless to say, without the nationalist elements within the Germans, similar cultures as well as economic growth, Bismarck may not have succeeded in unifying Germany. In other words, the unification of Germany proves that Bismarck united the German empire accordingly to events.
