If we imagine a German diplomat or general falling asleep in February 1914 and waking up today to see a prosperous Germany dominating a peaceful Europe, he would be pleased but not be surprised. The fall of the multiethnic Austrian Hungarian and Ottoman empires and their replacement by nation states was also predictable. No one in 1914 would have been astonished to learn that 100 years later Russia would remain an exporter of raw materials and its politics would be authoritarian, oligarchic, and corrupt. Britain’s half-hearted relationship towards the rest of Europe would startle no one. What would shock our German general is the realization that it took two brutal world wars and the rise and fall of communism to achieve this outcome. Disastrous defeat twice over did not impede Germany’s rise. . . .I think this is only true at a certain scale. Zoom in, and little details like wars in which millions die matter rather a lot to people's lives. Even something like where the Polish-German border is drawn can completely upend the lives of thousands of people.
On the one hand, even deeply important historical events can be seen as accidents or flukes. On the other, over the longer term history seems tied to the profound processes of demographics, technology, culture and institutions that have little to do with the actions of mere men. To put it another way, even if Christopher Columbus had never gone to sea, cassava would nonetheless be a staple crop in Africa today and a Nahuatl speaking emperor would not be ruling Mexico. If we explore the counterfactual and assume that World War I had not broken out in 1914 and so the Russian Revolution not occurred in 1917 and Hitler not come to power in 1933, we might still end up with a world pretty close to what we have today. I’m not sure what that tells us about the value of the study of history.
Zoom out even farther, and it becomes nonsense to say that "Germany" has some sort of character that endures throughout history; I doubt any generalization you might want to make about the Germans would apply to the ninth century.
Different things about life change at different speeds, so if you define an arbitrary period (1914 to 2014, say) you can always find some things that have not changed. But plenty has.