Claim: Luxembourg is headed by a Grand Duke, Henri, who has ruled since 2000.
Evidence: As a representative democracy with a constitutional monarch , it is headed by a Grand Duke , Henri , Grand Duke of Luxembourg , and is the world 's only remaining grand duchy.
Henri -LRB- Henri Albert Gabriel Félix Marie Guillaume born 16 April 1955 -RRB- is the current Grand Duke of Luxembourg , reigning since 7 October 2000.