Cathay language, the word Cathay was sometimes used for China, although increasingly only in a poetic sense, until the 19th century when it was completely replaced by "China". A person from Cathay (i.e., a Chinese person) was also written in English as a Cathayan or a Cataian. However the terms "China" and "Cathay" have histories of approximately equal length in English. The term is still used poetically. Cathay is more prevalent as proper noun in names, such as Cathay Pacific Airways or Cathay Hotel. The flagship airline of Hong Kong is called as such because the founders envisioned that one day,
Cathay his "Book on the Administration of the State", apparently as two separate countries (presumably, referring to the Liao and Song Empires, respectively). The name's currency in the Muslim world survived the replacement of the Khitan Liao dynasty with the Jurchen Jin dynasty in the early 12th century. When describing the fall of the Jin Empire to the Mongols (1234), Persian history described the conquered country as "Khitāy" or "Djerdaj Khitāy" (i.e., "Jurchen Cathay"). The Mongols themselves, in their "Secret History" (13th century) talk of both Khitans and Kara-Khitans. In about 1340 Francesco Balducci Pegolotti, a merchant from Florence, compiled the