In fact, France's feud is Austria (Burgundy succeeded to the throne, imperial territory) and Britain (see the Hundred Years' War for details).
So what was the initial contradiction between Germany and France?
1. Who owns Alsace Lorraine? Austria says it belongs to the Holy Roman Empire, and France says it belongs to France. In fact, this place belonged to the Holy Roman Empire from the beginning, and was later occupied by France several times, and then incorporated into the French territory through treaties and marriages. Well, belonging to France makes sense. But the problem is that later generations of Germany and France all think Alsace Lorraine is their own, which is troublesome.
2. In the Franco-Prussian War, France wanted to restore its hegemony in Europe, so after being angered, France took the initiative to attack Germany. But in fact, the German army was very effective, and France failed to get good results. France was counterattacked and returned to the mainland. However, after the Prussian army entered France, it was a full-scale invasion. Then the contract, France paid 5 billion francs, Germany recovered Alsace Lorraine (here again), and before the 5 billion francs were paid off, the Germans occupied six northern provinces. Prussia successfully unified the German states by means of war and established the German Empire. Those who could not be unified were already kicked out (Austria). Moreover, the establishment of the empire in the palace of Versailles, the French court, shows that the newly born Germany has replaced France's position in Europe and seriously trampled on France.
After World War I, France wanted Germany to be dismembered, but Britain and the United States disagreed. France, on the other hand, proposed very harsh conditions to punish Germany. Then Shuang Yi of France won Alsace Lorraine for the second time, and France wanted the Saar region. Sal's industry is developed, and the League of Nations is in charge of this area. The industry was handed over to France for development, and the environment in Sal was seriously damaged. Later, through a referendum, Saar returned to Germany, and Germany was in chaos.
4. In World War II, German Shuang Yi recaptured Alsace Lorraine twice, and then the empire fell. France won Alsace Lorraine once. Nothing has changed since then.
By the way, it's not new that the anti-French alliance has Prussia. The three Frederick kings of Prussia all had "fine traditions". To put it bluntly, whoever gives money to help who may even give money to Hei. And Britain took the lead in organizing the alliance, and Britain paid for the military. Moreover, for Prussia at that time, allies were for sale, and the key was to sell them at a good price. So why did the French Prime Minister say that "the German Empire was born in injustice and died in shame" after World War I? It is so wicked in history. Of course, Prussia has also pitted France.