There were four lines of expansion available to the Counts of Barcelona during the 11th century, given their geographical situation. They could expand northward to the Occitan countries, westward towards the lands of Lérida and Aragón, southward towards Tarragona and the Kingdom of Valencia or eastward towards the Mediterranean. The victories of Count Ramon Berenguer I (1035-1076) over the Moors at that time likewise contributed to his increased prestige among Christians. Although marriage links had previously been contracted between noble houses on both sides of the Pyrenees, it was Ramon Berenguer I who decisively launched a trans-Pyrenean policy (which until then had been vaguely expressed) in order to establish a comprehensive domain in southern Gaul. With this aim, in 1054 he married Almodis, daughter of the Counts of the Marche. Since then, the Counts of Barcelona took part in the political life of the counties in southern France, skilfully using to this end the large amounts paid in tribute by the Moors.
In 1066 the Count of Carcassonne and Razés (and Viscount of Béziers and Agde) died heirless. Both Ramon Berenguer I and his wife could claim rights to succession. In his will, Ramon Berenguer I left his children the counties of Carcassonne and Razés, the castle of Laurac and everything he had in the counties of Tolosa, Narbonne, Foix, Comminges and Sabarthes. Perhaps to reinforce his plans, Ramon Berenguer planned the marriage of his son Ramon Berenguer with Mafalda, daughter of Roberto Guiscardo, Lord of Sicily.
The bickering between the heirs of Ramon Berenguer I –which culminated in the assassination of Ramon Berenguer II, planned by his own brother– weakened the power of the Counts of Barcelona. After certain disturbances in the wake of the fratricide, Carcassonne remained in the possession of Bernat Ató, Viscount of Béziers (1083). In 1096, Ramon Berenguer III, grandson of Ramon Berenguer and son of Ramon Berenguer II and Mafalda, took over the County of Barcelona and resumed his grandfather's policy. He then demanded the return of his domains. The men of Carcassonne, faithful to the House of Barcelona, had submitted to Bernat Ató under the condition that when Ramon Berenguer III came of age he would be given back possession of the county. But Bernat Ató did not fulfil his commitment, backed by the Count of Toulouse and Alfonso I of Aragon. The claims were reiterated in 1105 and Carcassonne leaders staged a revolt against the viscount in 1107. However, this revolt coincided with the Almoravid invasion, so Ramon Berenguer III was scarcely able to send his supporters any help. In 1112, Ramon Berenguer III married Dolça, heiress of Provence, Millau, Gevaudan (or Gavaldà) and Carlat, thus winning support from the Viscount of Narbonne to his cause. The intervention of the archbishop of Narbonne (Dolça’s relative and Bernat Ató’s ally) allowed an agreement to be reached. Bernat Ató recognised ruling Carcassonne and its County as a fiefdom from the Count of Barcelona, and he granted Ramon Berenguer III twelve castles he owned in the South of France, castles which Ramon returned to Ató as a fief. Bernat Ató compensated the Count of Barcelona with a certain amount, and furthermore the possibility was foreseen of the Count of Tolosa making a claim, in which case Ramon Berenguer pledged that he would defend the viscount’s legal rights. As for the County of Razés, which Ató had bequeathed to King Alfonso I of Aragon to meet the Count of Barcelona’s claims, the parties agreed that if Alfonso died without children or if the Count of Barcelona took it back, then it would be handled in the same manner as Carcassonne.
The agreement of 1112 established a certain balance by legalising the previous situation, since Carcassonne and Razés remained in the hands of Ató, although the sovereignty still rested with the Count of Barcelona. However, this arrangement did not solve problems definitively. The Barcelona County’s ambitious trans-Pyrenean policy received a strong boost with Ramon Berenguer III. But this initiative did not earn the sympathies either of the Counts of Toulouse nor of the Kings of Aragon (united by family ties), nor of the Kings of France. Throughout the twelfth century, trans-Pyrenean politics would comprise the great focus of activity for the Counts of Barcelona and Kings of Aragon –in a struggle against the rival powers of France and Toulouse– until Muret’s defeat in 1213.
ACA, Royal Chancellery, Ramon Berenguer III, Parchments, Undated, no. 2