The Yuan Shi
The Yuan Shi is known to contain many errors. It is proven that many events after 1259 in Guo Kan's biography are false since he returned to Mongolia with Hulagu Khan after the death of Möngke Khan in China. Hulagu, according to Hayton, did not return to Mongolia, something which is supported by Gregor of Akanc in his "History of the Nation of Archers." Rashid al Din in his detailed account of Hulegu never refers to Hulegu returning to Mongolia either. Yet in poorly cited secondary literature, the story of Hulegu returning to Mongolia persists to this day.
The Yuan Shi in many ways resembled historical fiction, claiming all manner of conquests by Guo Kan which were not true, but nonetheless were legend in China for many years. Contrary to claims in the Yuan Shi, the Mamluks of Egypt crushed the Mongol occupation army and their Christian allies at Ain Jalut led by Hulagu's lieutenant Ked-Buka; and the Crusader Kingdoms Mecca and Cyprus were neither conquered by the Mongols. Moreover, Guo Kan's Yuanshi biography refers to him crossing the sea and subjecting the Fulang, which we know from other Chinese transcriptions, to be the Franks. This has been argued to be Cyprus by modern apologists, only because we know with certainty that Europe was not subdued by Guo Kan. Yet the history of Cyprus in the Middle Ages is also well-documented, and we know that it was not subjugated by the Mongols. Rather than admit that the account of Guo Kan's actions in 1259 and 1260 are largely fiction, modern apologists for the garbled biography of Guo Kan in the Yuanshi have attempted to demonstrate that the Fulang across the sea must be referring to Cyprus, the nearest Frank territory. In fact, the Yuanshi biography of Guo Kan clearly says that he subjugated the "Fulang" and multiple kings, suggesting the author was imagining that all of Europe was conquered. That account ends with "Thus the entire Western Regions were subjugated." In all likelihood, the Yuanshi author simply claimed that Guo Kan conquered all of Europe because it was so geographically and historically remote, that such a claim would not fall under scrutiny to a Chinese readership, nor were the facts entirely important.
This biography of Guo is mostly factually muddled in what seems to be an attempt to hide the crushing defeats inflicted on the Mongols at Ain Jalut, and on Hulagu by Berke Khan in the first Mongol on Mongol war in the Transcaucasus. Ain Jalut took place while Guo Kan was in Mongolia with Hulagu during the selection of a Great Khan. Of course, we must remember that not a single primary source from the period, including Rashid al Din, Hulegu's own letter to Louis IX, Vardan Areweltsi, Grigor of Akanc, Bar Hebbraeus, or any of the Mamluk biographies of Baybars mention Hulegu ever returning to Mongolia. Indeed, if Guo Kan, were with Hulegu in Mongolia, then this is not something that can be confirmed by any sources from the time. Guo Kan, like Hulagu, had believed the force left to occupy Palestine was sufficient enough to deal with the Mamluks, which it was obviously not, and that the Ilkhanate could defeat the Golden Horde, which it equally could not.
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