Yelü Diela

Yelü Diela (耶律迭剌), younger brother of Khitan Emperor Yelü Abaoji, invented the "Khitan small script" to accommodate the more agglutinative Khitan language about 925 — based partly on the earlier "Khitan large script" or Chinese-like logographic writing, but also after having been inspired by the vertically written Old Uyghur alphabet that was shown to him by an ambassador.