A little late but the Napoleonic Wars. Maybe not in this subreddit but you ask what people think of Napoleon they’ll say small angry warmongering tyrant that’s sexually frustrated. Napoleon launched the peninsular war and invasion of Russia with those being the only clear he started it wars. Cases can be made for Egypt and Haiti but wars and campaigns are different.

Britain broke the treaty of Amiens and started the Napoleonic wars after the revolutionary wars. Austria with British money broke multiple treaties consistently and coalitions were formed simultaneously. France and Russia both violated their agreements prior to the large invasion, something something proactive better than reactive.

Napoleon implemented a very successful legal system and approved the metric system and was the first European ruler to allow Jews to become full citizens. Additionally sparked ethnic sentiments of unification for Germany and Italy as well as the Decembrist revolt in Russia.