House of Haro

The House of Haro, [La Rioja|Haro] was one of the most powerful families of Castile during the Middle Ages, which strongly supported the expansionist policies of Alfonso VI of Castile. As a reward, Íñigo [López, Lord of Biscay|Íñigo López] was named the first Lord of Biscay.
In the early 16th century, the Haro family married paternally into the House of Sotomayor establishing a branch that would go on to hold dominion over the Marquesado del Carpio established in 1559 by King Philip [II of Spain].