Cathay

Cathay (/kæˈθeɪ/) is the Anglicized rendering of "Catai" and an alternative name for China in English. It originates from the word Khitan (Chinese: 契丹; pinyin: Qìdān), the name of a nomadic people who founded the Liao dynasty which ruled much of Northern China from 907 to 1125, and who later migrated west after they were overthrown by the Jurchens to form the Qara Khitai centered on today's Kyrgyzstan for another century thereafter.

Originally, Catai was the name applied by Central and Western Asians and Europeans to northern China; the name was also used in Marco Polo's book on his travels in China (he referred to southern China as Mangi).

The term Cathay came from the name for the Khitans. A form of the name Cathai is attested in a Uyghur Manichaean document circa 1000. The Khitans refer to themselves as Qidan, but in the language of the ancient Uyghurs the final -n or -ń became -y, and this form may be the source of the name for later Muslim writers. This version of the name was then introduced to medieval and early modern Europe via Muslim and Russian sources.

The Khitans were known to Muslim Central Asia: in 1026, the Ghaznavid court (in Ghazna, in today's Afghanistan) was visited by envoys from the Liao ruler, he was described as a "Qatā Khan", i.e. the ruler of Qatā; Qatā or Qitā appears in writings of al-Biruni and Abu Said Gardezi in the following decades. The Persian scholar and administrator Nizam al-Mulk (1018–1092) mentions Khita and China in his Book on the Administration of the State, apparently as two separate countries (presumably, referring to the Liao and Song Empires, respectively).

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