section_path: History/Byzantine Empire (6th–14th centuries)
section_name: Byzantine Empire (6th–14th centuries)
paragraph_text: Byzantine Empire (6th–14th centuries)
  
  Byzantine Greek historian Procopius stated that two Nestorian Christian monks eventually uncovered the way silk was made. From this revelation, monks were sent by the Byzantine Emperor Justinian (ruled 527–565) as spies on the Silk Road from Constantinople to China and back to steal the silkworm eggs, resulting in silk production in the Mediterranean, particularly in Thrace in northern Greece, and giving the Byzantine Empire a monopoly on silk production in medieval Europe. In 568, the Byzantine ruler Justin II was greeted by a Sogdian embassy representing Istämi, ruler of the First Turkic Khaganate, who formed an alliance with the Byzantines against Khosrow I of the Sasanian Empire that allowed the Byzantines to bypass the Sasanian merchants and trade directly with the Sogdians for purchasing Chinese silk. Although the Byzantines had already procured silkworm eggs from China by this point, the quality of Chinese silk was still far greater than anything produced in the West, a fact that is perhaps emphasized by the discovery of coins minted by Justin II found in a Chinese tomb of Shanxi province dated to the Sui dynasty (581–618).
  
  Both the Old Book of Tang and New Book of Tang, covering the history of the Chinese Tang dynasty (618–907), record that a new state called Fu-lin (拂菻; i.e. Byzantine Empire) was virtually identical to the previous Daqin (大秦; i.e. Roman Empire). Several Fu-lin embassies were recorded for the Tang period, starting in 643 with an alleged embassy by Constans II (transliterated as Bo duo li, 波多力, from his nickname "Kōnstantinos Pogonatos") to the court of Emperor Taizong of Tang. The History of Song describes the final embassy and its arrival in 1081, apparently sent by Michael VII Doukas (transliterated as Mie li yi ling kai sa, 滅力伊靈改撒, from his name and title Michael VII Parapinakēs Caesar) to the court of Emperor Shenzong of the Song dynasty (960–1279).
  
  However, the History of Yuan claims that a Byzantine man became a leading astronomer and physician in Khanbaliq, at the court of Kublai Khan, Mongol founder of the Yuan dynasty (1271–1368) and was even granted the noble title 'Prince of Fu lin' (Chinese: 拂菻王; Fú lǐn wáng). The Uyghur Nestorian Christian diplomat Rabban Bar Sauma, who set out from his Chinese home in Khanbaliq (Beijing) and acted as a representative for Arghun (a grandnephew of Kublai Khan), traveled throughout Europe and attempted to secure military alliances with Edward I of England, Philip IV of France, Pope Nicholas IV, as well as the Byzantine ruler Andronikos II Palaiologos. Andronikos II had two half-sisters who were married to great-grandsons of Genghis Khan, which made him an in-law with the Yuan-dynasty Mongol ruler in Beijing, Kublai Khan.
  
  The History of Ming preserves an account where the Hongwu Emperor, after founding the Ming dynasty (1368–1644), had a supposed Byzantine merchant named Nieh-ku-lun (捏古倫) deliver his proclamation about the establishment of a new dynasty to the Byzantine court of John V Palaiologos in September 1371. Friedrich Hirth (1885), Emil Bretschneider (1888), and more recently Edward Luttwak (2009) presumed that this was none other than Nicolaus de Bentra, a Roman Catholic bishop of Khanbilaq chosen by Pope John XXII to replace the previous archbishop John of Montecorvino.