Sobrarbe was one of the Christian principalities of the Marca Hispanica, with obscure origins.
Legend says there was a Kingdom of Sobrarbe, where a cross appeared upon a tree Latin: Supra Arbore.

It became part of the County of Aragon, but in the early 9th century was held for five years by Amrus ibn Yusuf, the governor of Zaragoza, being retaken after his death.
Sobrarbe was joined to the County of Ribagorza in the early 10th century through the marriage of Bernard I of Ribagorza to Toda Galíndez of Aragon, daughter of Galindo Aznárez II.
However, in the late 10th and early 11th century, a series of incursions from the south left it disorganized and depopulated, and for a time it again fell under Muslim control.
This was reversed by Sancho the Great of Pamplona, who reconquered the region in 1015, similarly extending his power into Ribagorza over the subsequent years.
Whatever hereditary claim might have existed was subsequently brought to Sancho through his wife Muniadona of Castile, heiress to the Ribagorza counts.

Sancho divided the territories he had united, and his third son, Gonzalo, was given the counties of Sobrarbe and Ribagorza.
After the death of Gonzalo in 1038, his illegitimate half-brother Ramiro I of Aragon brought Sobrarbe and Ribagorza into his hands, creating the nucleus of the Kingdom of Aragon.
Sobrarbe was one of the Christian principalities of the Marca Hispanica, with obscure origins. Legend says there was a Kingdom of Sobrarbe, where a cross appeared upon a tree Latin: Supra Arbore.
It became part of the County of Aragon, but in the early 9th century was held for five years by Amrus ibn Yusuf, the governor of Zaragoza, being retaken after his death. Sobrarbe was joined to the County of Ribagorza in the early 10th century through the marriage of Bernard I of Ribagorza to Toda Galíndez of Aragon, daughter of Galindo Aznárez II. However, in the late 10th and early 11th century, a series of incursions from the south left it disorganized and depopulated, and for a time it again fell under Muslim control. This was reversed by Sancho the Great of Pamplona, who reconquered the region in 1015, similarly extending his power into Ribagorza over the subsequent years. Whatever hereditary claim might have existed was subsequently brought to Sancho through his wife Muniadona of Castile, heiress to the Ribagorza counts.
Sancho divided the territories he had united, and his third son, Gonzalo, was given the counties of Sobrarbe and Ribagorza. After the death of Gonzalo in 1038, his illegitimate half-brother Ramiro I of Aragon brought Sobrarbe and Ribagorza into his hands, creating the nucleus of the Kingdom of Aragon.
Sobrarbe