Before the 20th century, in Europe at least, the "big" historical event that attracted a lot of popular attention as well as a lot of amateur history buffs was the Napoleonic Wars.

It's not uncommon in my field (late 19th c. Europe) to come across references in letters or diaries to key battles or events in the Napoleonic wars--70 or 80 year later.

The names of generals like Ney, Murat, Blücher, and of course Wellington and Nelson were as famous then as Patton, Rommel, Guderian, or Eisenhower are today. Interestingly, it was the French generals--and Napoleon himself, of course--who tended to be more 'famous' than the British, Austrian, or Russian leaders... probably due to France's aggressive expansion and impressive battlefield victories. And much like the German generals are more well known than their opponents. (The general public is more likely to have heard of Rommel than of Zhukov or Montgomery, for instance...)

Meanwhile, the German General Staff fought and re-fought the Napoleonic battles as a main element of their wargaming.

And of course, memorials and statues to the Napoleonic War were everywhere, all over Europe, commemorating generals, battles, and the dead.

Commercialized popular culture piggy-backed on this: scenes and heroes of the Napoleonic Wars were often the subject of popular prints (for collecting or decorating) like the Image d'Épinal (French) and the Bilderbogen (German).

The children's toy boom after the 1860s (with many manufacturers in German principalities) included lots of tin soldiers... and these were most often Napoleonic War figurines. (Though by the 1880s, they were as likely to be Wild West figurines, interestingly enough, given the huge popular interest in the Wild West in Germany and to a lesser degree France and England.)

A good book on this (though it only scratches the surface of a huge topic) is:

Alan Forrest, Etienne François, and Karen Hagemann's War Memories: The Revolutionary and Napoleonic Wars in Modern European Culture