The Imamate was bounded in the east by the Hajar Mountains and in the west by the Rub' al Khali (Empty Quarter) desert.

[3] The Imamate is a 1,200-year-old system of government pioneered by the Ibadi religious leaders of Oman, and was based upon the Islamic sharia.

Many of the Azd who settled in Basra became wealthy merchants and under their leader Muhallab bin Abi Sufrah started to expand the influence of power east towards Khorasan.

Ibadi Islam originated in Basra with its founder Abdullah ibn Ibada around the year 650 CE, which the Azd in Iraq followed.

[3] Since its appearance, the Imamate governed parts or the whole of present-day Oman and overseas lands for interrupted periods of time.

[12] The Omanis in the interior believed that the ruler should be elected and rejected growing British political and economic control over Muscat and Oman.

Sultan Said Bin Taimur of Muscat, with the direct support from the British forces, was able to defeat the Imamate in Jebel Akhdar War that lasted until 1959.

[11] In current usage, "Oman proper" can also refer to the whole of the present-day sultanate minus the exclaves of Musandam and Madha.