The building al-Mutawakkiliyya marked the high point of the expansion of Samarra; al-Ya'qubi reports that there was continuous development between al-Ja'fari and Balkuwara, extending a length of seven ''farsakh''s (42 km). Despite the significant amount of money spent to construct it, however, al-Mutawakkiliyya was occupied for only a very short time. Al-Mutawakkil took up residence in al-Ja'fari in 860 and transferred the government bureaucracies (''diwan''s) from Samarra, but following his assassination in December 861, his son and successor al-Muntasir ordered a return to Samarra and took up residence in the Jawsaq palace instead.