Even in the ages before the old empire, there is evidence that the pandaren love of learning had created epic poems, agriculture, and medicine. The Thunder King saw great potential in the pandaren, and for this reason he did not trust them. After he conquered the land, the pandaren were forbidden to learn to read or write. Their leaders and philosophers were executed. All pandaren art and literature was burned. Anyone caught speaking anything but the mogu tongue was considered to be a conspirator, a charge often punished with death.
All of the work of the earliest pandaren artists and writers has been lost forever. Ages later, other great pandaren scholars would be born... but the language they spoke was not truly their own.