I have complained about it before but I heard on of the guests from guerrilla history on the deprogram make this argument and it made me want to gouge my eyes out. This kind of trans historical argumentation is both stupid and unmarxist, just stop! Sorry I felt the need to vent.
These states were not imperialist and they weren't settler colonies. This framing doesn't make any fucking sense when transfered to a medieval context. Like the best you could say is that the Italian city states represented an early firm of merchant capital, but even then that is an incredibly complex phenomenon that has only a tenuous connection to modern capitalism. Calling these city states early capitalism is just a fancy way of saying "lol u hate capitalism yet you exchange good or service! Curious!"
Seriously just stop. I don't know why this set me off but it was like a week ago and I am still mad about it.
Keep in mind we are talking about a material historical process that lasted hundreds of years and then effectively died out several hundred before the material advent or European empires, which in turn reinterpreted and repurposed the history of the crusades for its own ideological justification. If the crusades created the concept of a unified conception "west" it sure didn't keep Europeans from creating hundreds of political formations to better kill each other over the next thousand years.