Background
Al-Husayn bin al-Qasim was a grandson of the imam al-Mu'ayyad Muhammad I (d 1644).
Al-Husayn bin al-Qasim was a grandson of the imam al-Mu'ayyad Muhammad I (d 1644).
He took advantage of popular discontent with the current imam al-Mahdi Muhammad. He claimed the imamate in the strong fortification Shaharah in 1716, taking the name al-Mansur. A large part of the country quickly fell away from the unpopular al-Mahdi Muhammad.
Al-Mahdi Muhammad had to give up and sue for a truce. Al-Mansur al-Husayn began to strike coins in his own name. However, already in the same year 1716 a-Qasim turned against the new imam, and proclaimed himself with the name al-Mutawakkil al-Qasim.
He controlled San'a and the seaports, while al-Mansur al-Husayn merely held Shaharah and some surrounding territories. Blocked from the sources of revenue, he led a meagre existence until he died in 1720.