Abd-ar-Rahman III
In 937, King García allied himself with Ramiro II of León and Muhammad ibn Hashim, governor of Zaragoza, resulting in a military campaign by Abd-ar-Rahman III via Calatayud and Zaragoza into García's lands. He participated in July 939 in the Battle of Simancas alongside Ramiro II and Fernán González with the Christian armies defeating the caliphal forces. After this reversal, Abd-ar-Rahman III was planning another expedition for March 940 but suspended all plans when he received a messenger from Ramiro II to negotiate a truce. The Caliph, in response, also sent an envoy to the Leonese court for the negotiations. At about the same time or sometime before, he had also begun talks with Sunyer, Count of Barcelona, the result of which was a two-year truce. The accord, very advantageous for the Christians in commercial terms, included several conditions, one of which was the cancellation of the plans (or the annulment) of the marriage of King García with Count Sunyer's daughter. The peace negotiations between King Ramiro II and Abd-ar-Rahman III were not concluded until the summer of 941. The peace included "all the frontier communities between the kingdoms of Leon and Pamplona, from Santarém to Huesca since Ramiro had a great interest in including García Sánchez I, the king who governed the destinies of the Pyrenean kingdom, rather than leaving him in the hands of Abd-ar-Rahman as the only Christian ruler remaining in a state of war with the Cordoban caliphate".