If I was able to be present at one historical event, I would choose the Battle of Austerlitz, (and on the French side, lol) The reason I would choose the Battle of Austerliz, is because of how Napoleon uses his troops to defeat a much more larger army. Because of how he conducted his troops and had a good grasp of what the enemy was like, taking hold of key positions, and using every natural thing there too his own advantage. He also kept his troops morale up, and trained them well, which enabled them to stand their ground and fight amid enemy attacks. Napoleons brillianteness in this battle made a turning point in how wars were fought, and it would always be known as Napoleons greatest victory
hope this helps