The film itself
Napoleon - 'Soldiers of the fifth. Do you recognise me?
[pause] If you want to kill your Emperor? Here I am.'
Müffling arrives at the ball, Wellington makes his plans (and we get the famous 'humbugged' lines), and afore ye know it, the troops are deploying on the battlefield.
The movie dutifully (and spectacularly) covers most of the major actions: the opening 'feint' against Hougoumont, D'Erlon's massed infantry attack, with the British/Allied cavalry charge riposte, many bombardments of the batteries (Bondarchuk seems to have had a 'thing' for artillery scenes!), the French cavalry washing around Allied squares, the arrival of the Prussians, and the final attack of the Guard, etc.
The scale of the production is truly amazing. Legend has it that for the duration of the filming of the battle scenes the multinational multilingual army assembled for the film was amongst the largest 'standing armies' in Europe. The bulk of the extras were Russian soldiers, and troops were drilled according to contemporary 'evolutions'. The battlefield was recreated pretty meticulously, in the Ukraine.
The cast is pretty stellar; Rod Steiger's Napoleon is actually very good. I must admit I didn't like him in the role instantly. But the more I watch the film, the better I think he is. Christopher Plummer is great as a very charming if somewhat clichéd aristocratic Wellington, and many of the supporting roles are well cast/played (the actor playing Blücher looks exactly right!).
Bondarchuk's direction is, on the whole, excellent, and clearly no expense was spared staging and filming the amazing battle scenes. Appropriate use is made of contemporary martial music, and the stirring menacing score, which helps build tension as we approach the battle, is also worthy of mention.
Sadly, despite all that it has going for it, the film didn't do as well at the box office as was anticipated, and that's not helped Napoleon reach the big screen (or little screens either, for that matter) in the years since. How different the situation is on the literary front, where there's a seemingly inexhaustible Krakatoa of works that continually belch forth on this perennially popular subject!
Would that someone with pots of of money might take the whole era on! My dream team would be: Spielberg, Jackson and Scott, sharing roles as executive producers, and poss even as co-directors, with Scott (his film The Duellists is one of the most beautiful depictions of the Napoleonic era) as production designer. And they could use Kubrick's researches, so he could get a credit as the ghost in the machine!
An extended director's cut?