The Byzantines and Fatimids entered into peace negotiations in 1032 and Hassan was present in the discussions in Constantinople.[1] The Byzantines stipulated the restoration of Jarrahid governorship in Palestine under Fatimid suzerainty as a condition for peace, but az-Zahir refused.[1] The Fatimids' rejection of this condition contributed to the collapse of the peace talks.[2] The following year, the Jarrahids offered their loyalty to al-Dizbari in exchange for their former iqtaʿat in Palestine, but the attempt failed.[16] The Fatimids and Byzantines ultimately concluded a ten-year peace treaty, without consideration of the Jarrahids' interests, in 1035.[17] Afterward, Hassan and his son Allaf are mentioned on occasion, such as their assistance in the Byzantine defense of Edessa from the Marwanids and Numayrids in 1035/36.[1] In 1038, the Jarrahids participated in al-Dizbari's conquest of Mirdasid-held Aleppo.[18] As a result, Hassan was forced into confinement in Constantinople until 1040 as a means to prevent his tribe, with its unstable allegiances, from potentially attacking Antioch.[18] The last mention of Hassan is in 1041, by which point the Jarrahids had been permitted by the Fatimids to re-enter Palestine.[1][18] Hassan's rule at the time was opposed by the Fatimid governor of Damascus.[1]