Gascon Suzerainty
Sancho established relations with the Duchy of Gascony, probably of a suzerain–vassal nature, him being the suzerain. In consequence of his relationship with the monastery of Cluny, he improved the road from Gascony to León. This road would begin to bring increased traffic down to Iberia as pilgrims flocked to Santiago de Compostela. Because of this, Sancho ranks as one of the first great patrons of the Saint James Way.
Sancho VI of Gascony was a relative of Sancho of Navarre and he spent a portion of his life at the royal court in Pamplona. He also partook alongside Sancho the Great in the Reconquista. In 1010, the two Sanchos appeared together with Robert II of France and William V of Aquitaine, neither of whom was the Gascon duke's suzerain, at Saint-Jean d'Angély. After Sancho VI's death in 1032, Sancho the Great extended his authority definitively into Gascony, where he began to mention his authority as extending as far as the Garonne in the documents issued by his chancery.
In southern Gascony, Sancho created a series of viscounties: Labourd (between 1021 and 1023), Bayonne (1025), and Baztán (also 1025).
Read more about this topic: Sancho III Of Navarre