Overview
The document is thought to be extremely comprehensive and very specific although no copies or even parts of copies survive.However copies have said to have been discovered in Korea, moreover there are records of excerpts among many chronicles including Makrizi, Vartang, and ibn Batuta, among others. Thought to be written in the Uigur Mongolian script and scribed on scrolls, Yassa was preserved in secret archives and known only to and read by royal families. One reason why the Yassa was only to be read by a select few was because, beyond being a code of laws, it was a work that had profound philosophical, spiritual, and mystical elements.
It is thought to have outlined laws for various members of the community such as soldiers, officers, doctors, and so on. It also addressed and reflected Mongol cultural and lifestyle aspects, particularly those dealing with environmental matters. Death was the most common punishment, including for minor offenses. For example a soldier not picking up something that fell from the person in front of him would be put to death.
The main purpose was probably to eliminate social and economic disputes among the Mongols and future allied peoples. Among the rules were no stealing of livestock from other people, sharing food with travellers, no abduction of women from other families, and no defection among soldiers. It represented a day-to-day set of rules for people under Mongol control that was enforced strictly with very stiff punishments for violators.
People were free to worship as they pleased, as long as the laws of the Yassa were observed.
The word Yassa translates into "order" or "decree". The Yassa was written on scrolls and bound into volumes that could only be seen by the Khan or his closest advisors, but the rules were widely known and followed. This probably was to prevent the abuse of some clauses and to avoid utilization of execution as a means of judicial murder or elimination of enemies. There are references to a large codex which would indicate that many laws need not be included, given the separate volumes.
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