The Sichuan Basin and adjacent areas of the Yangtze watershed were a cradle of indigenous civilizations dating back to at least the 15th century BC, coinciding with the Shang in northern China. The region had its own distinct religious beliefs and worldview. The earliest culture found in the region through archaeological investigation is the Baodun culture (c.2700–1750 BC) excavated in the Chengdu Plain.[10][11]