I've heard people say that they believe that WWI would not have occurred without it. I understand the chip on France's shoulder about Alsace and Lorraine played a role but it seems as if Germany was fairly uninvolved in the imperialistic competition abroad? Maybe someone here with more knowledge would be able to clarify re: the gravity of the event.
The unification of Germany likely had little direct lead up to the First World War, largely because the beginning of WW1 is such a complicated and intricate situation as is, that, as you put it, in my opinion, it is hard to put the blame on any one country in particular. Of the 5 major combatants of the war (Germany, Austria-Hungary, France, Russia, and Britain), a lot of blame can be thrown on Germany and Austria, and rightfully so, but the initiation and conditions that allowed the war to take off were definitely pushed along by both France and Russia to their own extent, along with Serbia, and by the general tension between the European Powers.
The emergence of Germany in 1871 basically threw a whole new player into the European power scene. Whereas Europe was largely dominated throughout the centuries by Britain, France, and the Holy Roman / Austrian Habdsburgs, with temporary but major power holds by Spain, Sweden, and Russia throughout history, Germany sprang to life in the late 19th century, a brand new country that immediately became one of the most powerful on the continent. The predecessor, Prussia, a powerful and reputable country in its own right, shocked Europe when, in very quick succession, defeated three different countries, in three different consecutive wars, to masterfully unify all of the fragmented German states into one, large, German nation-state. The state of Prussia before the German Unification Wars, and then its handling of them, is very well summed up, in my opinion, by Christopher Clark in his book Iron Kingdom: The Rise and Downfall of Prussia, 1600-1947:
For nearly half a century after 1815, Prussia stood on the sideline of European Power politics, steering in the lee of the great powers, avoiding commitments and shying away from conflict. It avoided antagonizing its powerful neighbours. It acquiesced in Russian tutelage over its foreign policy. Prussia was the only major European power to remain neutral in the Crimean War (1854-6). To some, it even seemed that Prussia's status as a member of the concert of the great European Powers was obsolete. Prussia, a Times leader article observed in 1860, was
always leaning on somebody, always getting somebody to help her, never willing to help herself [...] present in congress, but absent in battles [...] ready to supply any amount of ideals or sentiments, but shy of anything that savours of the actual. She has a large army, but notoriously one in no condition for fighting. [...] No one counts on her as a friend; no one dreads her as an enemy. How she became a great power, history tells us; why she remains so nobody can tell.
And yet, within eleven years of this blistering appraisal, the Kingdom of Prussia has reinvigorated its armed forces, driven Austria out of Germany, destroyed the military might of France, built a new nation-state and transformed the European balance of power in a burst of political and military energy that astonished the world.
Whereas France enjoyed renown as one of the most populous nations of Europe for, well, most of European history, was now eclipsed by the sudden appearance of this massive German state. The new state of Germany was birthed into existence with one of the biggest populations in Europe, along with a massive industry, complex railway and transportation system, large amount of wealth, and adopted the might of the Prussian military. With the titan that was Bismarck at the helm, Germany threw a cog into the "Balance of Power" in Europe.
Yet, despite this, from 1871 until 1890, Germany proved to be docile and not as aggressive as its might and strength could have allowed her to be. Bismarck effectively helped prove that German security and European peace were one and the same thing when he used the Berlin Congress to mediate the post-war settlement of the Russo-Turkish War in 1878 with no reward for Germany. Bismarck's policy attempted to steer Germany out of the way for colonialism, and by 1887, his Bismarckian Alliance tied Germany to virtually every single European country. When Bismarck left the Chancellorship, he inevitably left a power vacuum that could not be filled, for there were little if any men of his stature to fill it.
The lead up to WW1 can be asserted with blame on both Austria and Germany, but also on France and Russia. The French in particular were the ones that were the most aggressive/hostile in their policy towards Germany. The matter of fact is that the sheer existence of Germany put Franco-German relations at high tensions. I would like to again quote Christopher Clark on the subject, this time from his other book, *The Sleepwalkers, How Europe Went to War in 1914", as he explains it much better than I ever could:
For centuries, the German centre of Europe had been fragmented and weak; now it was united and strong. The war of 1870 placed the relationship between Germany and France on a permanently difficult footing. The sheer scale of the German victory over France - a victory most contemporaries had not predicted - traumatized the French elites, triggering a crisis that reached deep into French culture, while the annexation of Alsace-Lorraine [...] - imposed a lasting burden on Franco-German relations. Alsace-Lorraine became the holy grail of the French cult of revanche, providing the focus for successive waves of chauvinist agitation. The lost provinces were never the sole driving force behind the French Policy. Yet, they periodically inflamed public opinion and exerted a stealthy pressure on policy-makers in Paris. Even without the annexation, however, the very existence of the new German Empire would have transformed the relationship with France, whose security had traditionally been underwritten by the political fragmentation of German Europe. After 1871, France was bound to seek every possible opportunity to contain the new and formidable power on its Eastern border. A lasting enmity between France and Germany was thus to some extent programmed into the European international system. It is hard to overstate the world-historical impact of this transformation.
This meant that ever since 1871, France would be at ends with Germany over many issues. Russia particularly became a central objective between the two powers. France wanted an alliance with Russia to gain a powerful and dependable ally against Germany on continental Europe, an ally that had the added benefit of encircling Germany on two fronts, and Germany wanted an alliance with Russia to specifically avoid this situation. Bismarck successfully built a Russo-German alliance during his chancellorship, which lasted into the 1890's. However, the nature of the alliance, which included Austria, inevitably left Germany with the problem of ultimately and eventually having to choose between Austria and Russia down the road due to the two countries having overlapping interests in the Balkans. When Bismarck left the chancellorship, Kaiser Wilhelm opted to stick with Austria, at which point the Russo-Germany alliance collapsed, and France swooped in and partnered with Russia. This lead to Germany being squished by France in the West and Russia in the East, all thanks to France's desire to gain an upper-hand over Germany.
On the other hand, Russia remained a large player in European politics in the lead-up to WW1. Seen in the Balkans, and by herself, as a protector of the Slavic peoples, Russia had became very involved in the affairs of Europe by the 20th century, particularly in the Balkans and with Austria. As mentioned before, the overlapping interests of Russia and Austria over the Balkans put the two at odds, and ever since Germany's closer ties to the Austrians, it put Russia at odds with Germany as well. The matter of the fact was that Russia's disastrous defeat in the Russo-Japanese war prodded it forward to modernize its military. A General staff was introduced, the army was modernized, the fleet was enlarged, and the military as a whole was improved. As the situation in the Balkans evolved, with Italy's participation in the Triple Alliance deteriorating to unreliability by 1913, and Romania evidently showing no interest in helping Germans or Austrians, Russia continually become more and more emboldened to press herself into the affairs of the Balkans. While nobody really knew, including the Serbians, 100% if Russia really would step in to protect Serbia in case of war, it soon became evident. After the July Crisis, Russia asserted its position as the "Protector of Pan-Slavism" by concluding that in the case of war between Austria and Serbia, she would come to the aid of the Serbians. In fact, Russia began to mobilize by July 30, forcing Germany to do the same.
To put it simply, the unification of Germany lead to an upheaval of European politics, and a major shift in the Balance of Power in Europe. It opened the door to animosity between Frenchmen and Germans, and eventually between Germans and the Russians as well. However, while its sole existence put it at odds with its neighbours, the animosity against Germany was warranted and pursued by said neighbours as much as it was pursued by Germany. The issue arose when the Austrians (with the backing of the Germans) attempted to instigate a localized war in the Balkans. However, the web of alliances and premature-mobilization of European armies across the continent made this impossible, leading to the First World War. In reality, it is hard to point to one single cause and blame it for causing the war. The conditions in Europe, caused and pushed along by France and Russia just like they were by Germany and Austria, made a European war almost inevitable by the mid 1910's.
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