The State of Shu was an ancient state in what is now Sichuan, China. Shu was based on the Chengdu Plain, in the western Sichuan basin with some extension northeast to the upper Han River valley. To the east was the Ba tribal confederation. Further east down the Han and Yangtze rivers was the State of Chu. To the north over the Qinling Mountains was the State of Qin. To the west and south were tribal peoples of little military power.