Chongqing is said to be the semi-mythical State of Ba that began in 11th century BC , when the Ba people began living here until they were destroyed by the State of Qin in 316 BC . Tradition associates Chongqing with the semi-legendary State of Ba that the Ba people supposedly established during the eleventh century BCE . By 316 BCE , however , it had been overrun by the State of Qin .