Mainstream works of Arabic-Islamic historiography produced during the ninth and tenth centuries present the frontiers of the caliphate as a zone of persistent Islamic expansion enabled by conquering governors. Provincial accounts, however, often present a different story. For example, in the 13th-century Persian text from Sind called the Chachn?ma, we find that members of an Arab group with the nisba al-'Ilaf?, probably referring to the Banu Jarm tribe of Omani origin, was already in Makr?n and Sind and even allying with Sind's ruler against the invading Muslim armies led by Muhammad b. al-Q?sim. The Chachn?ma also contains brief contradictory accounts according to which Muhammad b. al-H?rith al-'Ilaf? either refused to fight the Muslims or reconciled with them before the end. They are also completely absent from accounts of the conquest of Sind produced elsewhere. This highlights the difficulty Islamic historiography had absorbing apparent Muslims whose behavior on the frontiers did not conform to the expectations set by the fut?? historiographic theme. Al-Muhallab b. Ab? Sufra's governorship of Khurasan is a variation on this theme. His major campaign was a three-year siege of Kish, and our extant sources report criticism of him for not acting more aggressively toward that city or pressing on into Sogdiana. They also contain views attributed to al-Muhallab, including a claim that he advised his sons not to conquer Tirmidh so as to continue justifying their own control over the province. His reputation as a conqueror, however, may have been passed on largely through panegyric poetry such as the elegy of Nah?r b. Tawsi'a al-Taym? which both al-Tabar? and Ibn 'As?kir place as a capstone on their discussions of al-Muhallab's career. Omani Arabs in Sind were almost certainly there because of trade connections, and evidence suggests the Muhallabids frequently found collecting taxes from their provinces more worthwhile than expanding their realms. However, insofar as the frontier was conceived as a zone of conquest such activities had to be marginalized, hidden, or denied in in order to center a narrative of conquering heroes.