Bani Nabhan were one of the Arab tribes of the interior with an ascribed
Azdi origin. After the collapse of the Makramid dynasty, the Buyids appointed the Bani Nabhan as the governors of
Sohar. The Nabhanids retained their power under the transition to
Seljuk rule, and emerged as sovereign rulers after the waning of the Seljuk state. They eventually came to control cities in the interior such as
Nizwa and
Rustaq, but these were won back by the
Ibadi Imamate. in 2013 after major restoral work in the 1990s The best quality
frankincense, a valuable product in the Middle Ages, comes from
Dhofar in the interior of southern Oman. The Banu Nabhan controlled the trade in frankincense on the overland route via Sohar to the
Yabrin oasis, and then north to
Bahrain,
Baghdad and
Damascus. Muhammed al-Fallah of the Banu Nabhan emerged as a powerful leader in 1151 and had taken control by 1154. He lived until 1176. The Nabhans ruled as
muluk, or kings, while the Imams were reduced to largely symbolic significance. The Imams lost moral authority since the title came to be treated as the property of the dominant tribe at any time. According to the historian Sirhan bin Said there were no records of Imams from 1153, when Imam Musa bin Abu Ja'afar died, until 1406, when Imam Hubaise bin Muhammad died. The Nabhan came to make their capital at
Bahla. The
Bahla Fort is called Hisn Tammah, and is said to take its name from an Iranian ruler of the town before the Islamic period. The fort testifies to the power of the Nabhani in their heyday. The period is poorly documented. It seems that at times the Nabhani only controlled part of the interior of the country, and at other times also ruled over the coastal lands. The Oman suffered from Persian invasions, and at one point the coast was controlled by the
Kingdom of Hormuz. The Nabhan coordinated themselves politically with the Kingdom of Hormuz while they managed matters of the Omani interior. The Banu Nabhan were dominant over the other tribes until the end of the 15th century. There are records of personal visits by Nabhani rulers to
Ethiopia,
Zanzibar, the
Lamu Archipelago of what is now
Kenya, and
Persia. The al-Nabhani dynasty of
Pate Island in the Lamu Archipelago claimed descent from the Omani dynasty. ==Decline and fall==