Grand duchy
The only grand duchy in existence today is Luxembourg. Luxembourg became a grand duchy in 1815 when the Netherlands became an independent kingdom, and King William I of the Netherlands was made Grand Duke of Luxembourg. In 1890, the two countries separated.  William III of the Netherlands had no male heir, so in the Netherlands he was succeeded by Queen Wilhelmina but Luxembourg followed Salic law, which meant only a man could rule.  The present Grand Duke of Luxembourg is Henri.