Yassa

Yasser (alternatively: Yasa, Yasaq, Jazag, Zasag, Mongolian: Их засаг, Yehe Zasag) was a secret written code of law created by Genghis Khan. The word Yassa translates into "order" or "decree". It was the de facto law of the Mongol Empire even though the "law" was kept secret and never made public. The Yassa seems to have its origin as decrees issued in war times. Later, these decrees were codified and expanded to include cultural and life-style conventions. By keeping the Yassa secret, the decrees could be modified and used selectively. It is believed that the Yassa was supervised by Genghis Khan himself and his stepbrother Shihihutag who was then high judge (in Mongolian: улсын их заргач) of the Mongol Empire. Genghis Khan appointed his second son Chagatai (later Chagatai Khan) to oversee the execution of the laws.

The Yassa decrees were thought to be comprehensive and specific, although no Mongolian scroll or codex has been found. There are records of excerpts among many chronicles including Makrizi, Vartang, and ibn Batuta, among others. Moreover, copies may have been discovered in Korea as well. The absence of any physical document is historically problematic. Historians are left with secondary sources, conjecture and speculation, which describes much of the content of this overview. Historical certainty about the Yassa is weak compared to the much older Code of Hammurabi 18th century BCE or the Edicts of Ashoka, 3rd century BCE. The latter were carved for all to see on stone plinths, 12 to 15 meters high, which were located throughout Ashoka's empire (today's India, Nepal, Pakistan, and Afghanistan). The Yassa, thought to be written in the Uigur Mongolian script and scribed on scrolls, was preserved in secret archives and known only to and read only by the royal family. Beyond being a code of laws, the Yassa may have included philosophical, spiritual, and mystical elements, and thus may have been thought of as a quasi-sacred or magic text.

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