Hisham II ('ھشام) was the third Caliph of Córdoba, of the Umayyad dynasty. He ruled 976-1013 from the age of 20, at first from the help of Muhammad Ibn Abi Aamir, who he made Chancellor once Caliph and managed his estate since he was young. Muhammad, getting tired of running the country as second in command and not getting any younger, organised a coop with mercenaries from North Africa, which ultimately failed.
Hisham II, while with supporters knew that he couldn't take control of the situation and defeat Muhammad without help. He sent word to his Berber allies in North Africa, who was once helped by his grandfather Abd-ar-Rahman III to come with troops as soon as possible. If successful he promised the Berber people representation within the Caliphate of Córdoba, and set aside Muhammad's role as Chancellor as the prize. The Berbers responded, and did send troops. The Civil war, at that point in a stalemate resumed and went in favour of Hisham II. He kept his promise, and the Moorish-Berber union goes ahead.
Navarre and Barcelona, Christian nations to the north, were annexed later in Hisham II's rule. After his death, his son Hisham III takes over.