It is interesting to me that a good chunk of Western Europe was already united once before and fell apart again. You only really realize how large the territory he ruled over was when you find out in how many languages they have a localized name for him and that in general the impression was not so much of a conqueror (which he definitely was) but a uniter. And it's well over a thousand years ago.
edit: Oh, another funny thing: To this day there are people trying to trace their family linkage with Charlemagne, or "Karel De Grote" as he's called here.
Well, he was marketing himself as the uniter of the western roman empire which was still remembered around. also, many of those who considered him a conqueror didn't live long enough to pass their attitude.
I think one factor is the uncertainty about his birth date and place that lasted for centuries (some of it is still disputed) which allowed a lot of place to claim him 'as their own'. Even today people in Poland, Germany, The Netherlands, France, Austria, Belgium and as far away as Southern Europe believe that he was their countryman, speak well of him without knowing much of the detailed history of his reign and have all kinds of lore (stories, songs!) that refer to him. In the Netherlands we have him in all kinds of popular culture, including stories, songs, and even jokes, which kids tell each other without knowing who 'Karel de Grote' was!
Quite a lot of subsequent European history was attempts (with varying degrees of success and longevity) to unify chunks of it. Even before Charlemagne, Justinian tried to reconquer the west.
On the other hand some people think the fact that Europe was hard to unify lead to it period of dominance from early modern times to the 20th century.
Just down the road from Hamburg, the town hall in the city state of Bremen replaced its copper roof in 2016.
It was fascinating to see the shiny copper oxidize over a relatively short space of time.
https://www.rathaus.bremen.de/rathausdachsanierung-2016-3196...
Copper has the advantage that unlike iron, which will be consumed completely by rust when exposed to humid air, the oxidation speed slows down with an increasing thickness of the oxidized layer (formed of copper carbonates), until further oxidation becomes negligible.
This post brought back some good memories! I lived in hh for 3 years .. quite close to the rathaus in harvestehude .. and used to walk past it all the time on my way to buy cigars at la casa del habano in chilehaus .. its a stunning building, and the pics really dont do justice to just how massive and imposing it is in person ... even more impressive when u think it was built in the late 1800 ..
I first toured the Hamburg Rathaus shortly after playing the recent Indiana Jones game. My most salient observation was that the Rathaus interior was a dead ringer for the Vatican interior spaces in that game: Wide marble gilded and red-carpeted staircases, walls made of art and covered in art with bas-relief everywhere, even the same hardwoods used everywhere as far as I could tell.