Ironic Historical Happenings

Hey gang, happy Ides of March. As you all know, Julius Caesar was assassinated today.

To be assassinated today is ironic in itself, but did you know that Caesar was warned of his impending murder before it took place? According to Plutarch, that's exactly what happened. Imagine what would have happened if Caesar heeded the words of the soothsayer that warned him.

So, I was wondering if you guys also have interesting, ironic things that happened during the course of forever (or history, for short).