Before the Song Dynasty (A.D. 960-1279), Chinese people didn’t sit in chairs. They put a mat or a cushion on the ground, and sat with kneeling. Ancient Chinese people had many proprieties of sitting.
The normal sitting posture was kneel-sitting (跪坐). Not only ministers and common people, but also emperors, kings and monarchs, all sat with kneeling. If the sitting posture of someone was not kneeling-sitting, others would think that he was insolent.