Charles I of England/Scotland/Ireland deserves a special mention here. I greatly admire the way he maintained his dignity and self-respect at the end of his life during his show trial, but it never should have happened in the first place. His incredibly arrogance, taking every disagreement as a personal affront, his zealous hubris in an unlimited kingly power, turned his kingdoms, which had basically been peaceful since 1485, both in their hinterlands and with each other, into a 17th century Bosnia or Rwanda. More people in Britain died per capita than during World War I. Complete and total catastrophe. He wasn't a BAD man. He didn't have bad morals, but these great character flaws led to completely avoidable tragedy.
