Abu'l Qasim Ubaid'Allah ibn Khordadbeh (Persian: ابوالقاسم عبیدالله ابن خردادبه) (c. 820 – 912 CE), author of the earliest surviving Arabic book of administrative geography, was a Persian geographer and bureaucrat of the 9th century. The son of a wealthy Persian family in northern Iran, he was appointed "Director of Posts and Intelligence" for the province of Djibal in northwestern Iran under the Abbasid Caliph al-Mutammid (ruled 869–885 CE). In this capacity ibn Khordadbeh served as both postmaster general and the Caliph's personal spymaster in that vital province.
Around 870 ibn Khordadbeh wrote Kitĝb al Masĝlik w’al Mamĝlik (The Book of Roads and Kingdoms). In this work, ibn Khordadbeh described the various peoples and provinces of the Abbasid Caliphate. Along with maps, the book also includes descriptions of the land, people and culture of the Southern Asian coast as far as Brahamputra, The Andaman Islands, peninsular Malaysia and Java. The lands of Tang China, Unified Silla (Korea) and Japan are referenced within his work.
The book does not reflect a strong influence from Greek earlier works such as Ptolemy's. The work uses heavily Persian administrative terms, gives considerable weight to Pre-Islamic Iranian history, uses native Iranian cosmological division system of the world. These reflect the existence of Iranian sources at the heart of the work.
It is one of the few surviving sources that describes the Jewish merchant company known as the Radhanites.
Khordadbeh wrote other books. He wrote around 8-9 other books bon many subjects such as "descriptive geography" (the book Kitĝb al Masĝlik w’al Mamĝlik), "etiquettes of listening to music", "Persian genealogy", cooking", "drinking", "astral patterns", "boon-companions", "world history", "music and musical instruments". The book on music had the title Kitĝb al-lahw wa-l-malahi which is on musical matters of Pre-Islamic Persia.
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- Meri, Josef W.; Bacharach, Jere (2005). Medieval Islamic Civilization: An Encyclopedia. Routledge. ISBN 0415966906. pp. 359-60.
- Adler, Elkan. Jewish Travellers in the Middle Ages. New York: Dover Publications, 1987.
- Bendiner, Elmer. The Rise and Fall of Paradise. New York: Putnam Books, 1983.
- Bareket, Elinoar. "Rĝdhĝnites". in Jewish Civilization: An Encyclopedia. Norman Roth, ed. Routledge, 2002. pp 558–561.
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- Gil, Moshe. "The Radhanite Merchants and the Land of Radhan." in Journal of the Economic and Social History of the Orient 17:3 (1976). 299-328.
- Israeli, Raphael. "Medieval Muslim Travelers to China" in Journal of Muslim Minority Affairs, 2000
- List of Iranian scholars