Khitan large script
Prior to their conquest of north China and the establishment of the Liao dynasty, the Khitans had no written language. In 920 the first of two Khitan scripts, the Khitan large script, was developed. A second script, the Khitan small script, was developed in 925. Both scripts are based on the same spoken language, and both contain a mix of logographs and phonographs. Despite surface level similarities to Chinese characters, the Khitan scripts are functionally unintelligible to Chinese readers, and neither scripts have been fully deciphered to this day.