In theory, the title of Caliph is given to the greatest combatant among the Children of Haqim, though few Caliphs have been masters of every form of combat. The supreme warlord's primary duties are to advise the Eldest on matters that pertain to the defense of the Children as a whole, and to guide the Warrior caste in its defense of the clan, its holdings, and its mortal subjects.
Additionally, should a trial by single combat arise whose outcome affects the entire clan, the Caliph is the Cainite who fights on the Children's behalf. No records of such an event exist, though the fact that this is the duty of the Caliph suggests that such circumstances arose at least once before.
In abstract, these duties make the Caliph the leader of the largest organized body of immortal soldiers and assassins in the world. In reality, the Caliph is simply holding the leash of a predatory clan who may or may not obey any particular suggestion he gives them. Wise Caliphs choose to guide rather than command, lest those predators turn on the leash-holder.
According to Warrior caste tradition, any Warrior who feels that the current Caliph is failing to discharge his duties may challenge the Caliph to a duel for leadership. However, the Caliph has the right to choose whether the challenge will be one of unarmed combat, armed combat, tactical leadership, or even strategic military command. Some Black Hand analysts believe that the tank battles of the 1973 Arab-Israeli War had some role in the last challenge to the Caliphate, though this theory is unproven.
If the current Caliph is defeated, he is expected to submit to ritual diablerie at the fangs of his challenger. Some newly minted Caliphs have allowed their predecessors the option of suicide by facing the rising sun from the side of the mountain that houses the Alamut. Challengers who meet defeat have always been consumed by the Caliph, and each of their descendants is given the choice of destruction or exile. This ensures that challenges do not come frivolously, as the childer of a challenger have been known to pull him down themselves rather than risk the consequences of a failed challenge.
- Mohara - Caliph during the Dark Ages. The practice of tithing 20% to one's clan elder is attributed to him
- Jamal - Caliph of Alamut until 1496, when he became the Eldest
- Thetmes - replaced an unknown Caliph after a failed assault on the Tremere Vienna Chantry
- Elijah Ahmed - childe of Thetmes, was Caliph until the early 2000s. Killed by Ur-Shulgi when he awakened from torpor
Currently, the position of Caliph is vacant, following Ur-Shulgi's destruction of the previous holder. However, several loyalist Warriors have tentatively advanced themselves as possible claimants, and it seems to be only a matter of time before actual conflict erupts.