Yelü Diela

Yelü Diela (Chinese: 耶律迭剌) was the younger brother of the Liao dynasty founder 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.