Answer:
Milan grow to be an important city-state in italy Thanks to its military force.
Step-by-step explanation:
First, Milan was founded by Celts and then conquered by the Roman empire, then Charlemagne, the franks, the Germans and many others. Almost all of the European empires conquered Milan at one point, however also the no-European powers that conquered Europe like the Huns and the Constantines also did it. Thus, Milan became a very strong and resistant state that fought for independence many times or that fought to defend itself from conquest.
Second, after all that war Milan became an independent solid-state that fought many Italian cities including the Vatican states. Making it the unifier of many of the Italian empire.
However, here is a point to considerate. Milan has a lot of merchants and is rich. It is also well-positioned in the geographical specter. Nevertheless, this was not a determining factor to make it as important as it is.
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