Sykes' History of Persia Vol 2 (pdf) - Heritage Institute

Father of Hasan, Father of Dust, The Victorious Lion of Allah, The Commander
of the Faithful, AH son of Abu Talib, on Him be Peace !
THE TITLES OF ALL
(Through the courtesy of H.E. the Persian Minister.)
CHAPTER XLVI
ISLAM UNDER THE FIRST FOUR CALIPHS
Politically Persia ceased for a while to enjoy a separate national existence,
being merged in that great Muhammadan Empire which stretched from
Gibraltar to the Jaxartes, but in the intellectual domain she soon began to
assert the supremacy to which the ability and subtlety of her people entitled
her.
BROWNE.
The Period of the Caliphate, A.D. 632-1258. The
Caliphate began with the election of Abu Bekr in A.D. 632
and lasted until A.D. 1258, when Hulagu Khan sacked
Baghdad and put Motasim Billah to death. For nearly
three centuries after this catastrophe the title of Caliph
was perpetuated in Egypt by descendants of the House
of Abbas who lived under the protection of its Mameluke
rulers, until in A.D. 1517 Sultan Selim, the Osmanli, having
conquered the Mameluke dynasty, induced the helpless
It is
Caliph to transfer to him the title and insignia.
on this transaction (recorded in Chapter LXII.)
that the
Sultans of Turkey base their claim to the sacred position
of Caliph and to other high
titles.
The Caliphate falls into three well-defined periods
:
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