If so, what were the pillars of said identity? And if there wasn't one, how did the identity of post-1871 Germany (strictly referring to the German Empire here, not Weimar or the Third Reich) come about? And final question: how does the Holy Roman Empire fit into German history? I know it can't be seen as a predecessor to the idea of "Germany" but I'd like to know its legacy and meaning for the German Empire and its character/identity.
My two cents, short version, will give any sources when asked but not near my bookshelf at the moment:
There was a German National ID inasmuch as the shared history that ties back to the HRE. Yet the states themselves had already been reorganised by Napoleon, 1848 had been a in damp squib in Prussia while Metternich kept the old order going as best he can until he gets the "heave ho" in '48. So Austria and Prussia had been the power blocs that
Post '71 the German Conscious was united along the lines of overcoming France, the common enemy. The Declaration of the Empire in the hall of mirrors was the focal point of this. Bismarck had to give his normal teutonic Johnson treatment to the "petty princes" of the lesser states to make them agree to his designs and coerce elderly Wilhlem I to accept the Crown. There was still State rivalries especially between North and South, the Bavarians seen the Prussian way of life as: “Join the army, pay your taxes, shut your gob.”