From what I thought was right before, the Franks settled in Gaul and the Alemanni conquered a lot of central Europe/ northern and central Italy/ Frankish Gaul and made the Holy Roman Empire under Charlemagne. Now I'm learning that Charlemagne was ruler of the Franks, but that means the Franks made the HRE. But the Franks made France right? So why did the French hate the German peoples if the Franks (future French) made the HRE? And how do the Alemanni fit into this?
Charlemagne, at his death, ruled an Empire encompassing modern day France (sans Brittany), the Pyrenees, Austria, Switzerland, the low countries, the northern half of Italy, and the majority of modern Germany. After his death, his son Louis I came to power, then died leaving his three sons to divide up his Empire, which they did in 843 with the Treaty of Verdun. Charles the Bald was given West Francia (modern France without Provence or Brittany), Lothair (the eldest) was given a strip of land encompassing the low countries, Burgundy, Provence, and northern Italy, and Louis the German was given the eastern territories (East Francia). Here's a map to clarify things. East Francia and parts of Lotharingia developed into the Holy Roman Emperor.
The traditional dislike between the French and the Germans come from more recent sources (such as the Napoleonic wars, the Franco-Prussian war, and the two World Wars).