Twenty-five years of personal rule by the second queen of this name led to her deposition in the Revolution of 1868, long after her accession to the throne provoked the Carlist wars.  
One English queen by this name married Richard II at the age of eight and was the elder sister of Catherine of Valois.  Another, known as the "she-wolf of France," was the mistress of Roger Mortimer, opponent of the Despenser marcher lords, and conspirator in the death of her husband, Edward II.  Twenty-five years of personal rule by the second queen of this name led to her deposition in the Revolution of 1868, long after her accession to the throne provoked the Carlist wars.  FTP, identify the name most famously held by the Castilian wife of Ferdinand II of Aragon.
One English queen by this name married Richard II at the age of eight and was the elder sister of Catherine of Valois.  
Isabella