Around the year 1200, Alfonso began to claim that the duchy of Gascony was part of Eleanor's dowry, but there is no documented foundation for that claim. It is highly unlikely that Henry II would have parted with so significant a portion of his domains. At most, Gascony may have been pledged as security for the full payment of his daughter's dowry. Her husband went so far on this claim as to invade Gascony in her name in 1205. In 1206, her brother John granted her safe passage to visit him, perhaps to try opening peace negotiations. In 1208, Alfonso yielded on the claim. Decades later, their great-grandson Alfonso X of Castile would claim the duchy on the grounds that her dowry had never been fully paid.