Liubo 六博 is an ancient Chinese board game for two players.
Historians have determined that it was invented no later than the middle of the 1st millennium BCE - being popular during the Han dynasty (202 BCE – 220 CE).
Since the boards were often made of bronze and ceramics, many well-preserved examples have been found. Mostly in ancient tombs of (male) Chinese subjects.
Exact descriptions of the rules of the game are unknown. There are various explanations in ancient Chinese texts, but they tend to contradict each other.
See Wikipedia
General info (with photos) courtesy V.R.Parton
Technical info on history and possible rules Oriens Extremus 55:105-166