20. Prince of Liechtenstein $3.5 Billion
Reigning Prince and legal head of state of Lichtenstein has been ruling since 1989.Prince Johannes Adam Ferdinand Alois Josef Maria Marko d’Aviano Pius von und zu Liechtenstein is the richest European Monarch, and the head of LGT banking group. His reign and power are widely unchecked, and formal day-to-day politics have been in charge of his eldest son Prince Alois since 2004. He has net worth of $3.5 billion!