owe their local Khalifate
far more to the out-of-the-way position of their country which prevented
Abbasids and Turks from meddling with their affairs. Otherwise, they would
have been obliged at any rate to acknowledge the sovereignty of the Great
Lord of Constantinople. This was the case with the Sherifs of Mecca, who
ever since the twelfth century have regarded the sacred territory as their
domain. Their principality arose out of the general political disturbance
and the division of the Mohammedan empire into a number of kingdoms, whose
mutual strife prevented them from undertaking military operations in the
desert. These Sherifs raised no claim to the Khalifate; and the Shi'itic
tendencies they displayed in the Middle Ages had no political significance,
although they had intimate relations with the Zaidites of Southern Arabia.
As first Egypt and afterwards Turkey made their protectorate over the holy
cities more effective, the princes of Mecca became orthodox.

The Zaidites, who settled in Yemen from the ninth century on, are really
Shi'ites, although of the most moderate kind. Without striving after
expansion outside Arabia, they firmly refuse to give up their own Khalifate
and to acknowledge the sovereignty of any non-Alid ruler; the efforts of
the Turks to subdue them or to make a compromise with them have had no
lasting results. This is the principal obstacle against their being
included in the orthodox community, although their admission is defended,
even under present circumstances, by many non-political Moslim scholars.
The Zaidites are the remnant of the original Arabian Shi'ah, which for
centuries has counted adherents in all parts of the Moslim world, and some
of whose tenets have penetrated Mohammedan orthodoxy. The almost general
veneration of the sayyids and sherifs, as the descendants of Mohammed are
entitled, is due to this influence.

The Shi'ah outside Arabia, whose adherents used to be persecuted by the
official authorities, not without good cause, became the receptacle of all
the revolutionary and heterodox ideas maintained by the converted peoples.
Alongside of the _visible_ political history of Islam of the first
centuries, these circles built up their evolution of the _unseen_
community, the only true one, guided by the Holy Family, and the reality
was to them a continuous denial of the postulates of religion. Their first
_imam_ or successor of the Prophet was Ali, whose divine right had been
un