Possibly one of the most important people in the history of the planet... but not for reasons he would like.

Wilhelm, born with a stunted arm, grew up with distant parents who frankly made his young life very difficult. They were, by the standards of the time, fairly liberal. So he, as a reaction, became incredibly conservative.

This might have been moderated in time but his father was diagnosed with incurable throat cancer shortly before taking the throne as the German Emperor (Kaiser). Instead of a couple of decades to calm down Wilhelm took the throne at a young age with a very strong authoritarian outlook on life.

He fricked Europe up on an unimaginable scale.

Germany had been the UK's pet project in Europe for decades. The Brits supported the unification, the wars, and the establishment of Germany's industrial might. But Wilhelm grew up jealous of the naval might his relatives in the UK enjoyed.

His favorite fantasy was that Germany would build a navy the equal of Britain and then they would be equals in the world. What he did not understand is that Britain had to have to the biggest and most powerful navy in the world because its army was, to put it mildly, petite. They had to control the sea, they couldn't control the land.

So he drove the UK into the arms of France and Russia, and by his bellicose statements gave Austria carte blanche to declare war on Serbia and start WWI.

Which, in turn, effectively destroyed the European empires. Sure, France and Britain more or less held onto their lands after the war. But they were beaten down as powers. Meanwhile Germany, Austria, and Turkey lost damn near everything.

As for Russia. Well. The Soviets took power and now their dedicated follower Putin is calling the shots and we know how that is going for them.

Wilhelm II effectively destroyed a world order that had been in place for 200 plus years.