Lord of Biscay is a historical title of the head of state of the autonomous territory of Biscay

Biscay

Biscay is a province of Spain and a historical territory of the Basque Country, heir of the ancient Lord of Biscay. Its capital city is Bilbao...

, Basque Country

Basque Country (autonomous community)

The Basque Country is an autonomous community of northern Spain. It includes the Basque provinces of Álava, Biscay and Gipuzkoa, also called Historical Territories....

.
The first known Lord of Biscay (11th century), Íñigo López

Íñigo López

Íñigo López was the first Lord of Biscay. Although the date is not known precisely, Íñigo's government of Biscay began between 1040 and 1043 at the latest. It was certainly by appointment of the king, García Sánchez III of Navarre, and not a hereditary right...

 "Ezkerra" was a lieutenant of the Kingdom of Pamplona (later known as Navarre

Navarre

Navarre , officially the Chartered Community of Navarre is an autonomous community in northern Spain, bordering the Basque Country, La Rioja, and Aragon in Spain and Aquitaine in France...

), and this was until the Castilian conquest of Gipuzkoa in 1200. The relations of the lords with the kings of Castille made them the landlords of Haro, La Rioja

Haro, La Rioja

Haro is a town and municipality in the northwest of La Rioja province in northern Spain. It is known for its fine red wine and every year the Haro Wine Festival is held where locals hold a wine battle....

 because they had favored the Castilian interests in the conflicts with Pamplona/Navarre.

The Lords had limited powers and had, like the Navarrese monarchs before them, to give oath at Gernika of respecting the fuero

Fuero

Fuero , Furs , Foro and Foru is a Spanish legal term and concept.The word comes from Latin forum, an open space used as market, tribunal and meeting place...

(Basque: forua) when inheriting the honor.

After the Lordship was inherited by the Castilian dynasty in 1370, the Kings of Castile and later Spain still have to give oath in equal manner, even after the Biscayan fueros were unilaterally supplanted in the 19th century as a retaliatory measure from Madrid for the support of the provinces to Carlist

Carlist Wars

The Carlist Wars in Spain were the last major European civil wars in which contenders fought to establish their claim to a throne. Several times during the period from 1833 to 1876 the Carlists — followers of Infante Carlos and his descendants — rallied to the cry of "God, Country, and King" and...

 pretender to the Crown..

• Jaun Zuria
  Jaun Zuria
  Jaun Zuria is the mythical first Lord of Biscay. According to the legend, he was born from a Scottish princess that had been visited by god Sugaar in the village of Mundaka....
  
   (the White Lord): supposedly born from the union of god Sugaar
  Sugaar
  In Basque mythology, Sugaar is the male half of a pre-Christian Basque deity associated with storms and thunder. He is normally imagined as a dragon or serpent. Unlike his female consort, Mari, there are very few remaining legends about Sugaar...
  
   and a Scottish (or Irish, or Danish, or Frankish) princess in the village of Mundaka
  Mundaka
  Mundaka is a town and municipality located in the province of Biscay, in the autonomous community of Basque Country, northern Spain. On the coast, Mundaka is internationally-renowned for its surfing scene....
  
  .