寶安縣
In 214 BC, when Emperor Qin Shi Huang unified China under the Qin Dynasty, the area went under the jurisdiction of the established Nanhai Commandery, one of the three commanderies that were set up in Lingnan, and was assimilated into Zhongyuan culture. In 331 AD, the Eastern Jin administration split up Nanhai and established a new (东官郡). The seat of both the commandery and Bao'an County, one of its six counties, was located around the modern town of Nantou. In 590, the Sui administration merged the region back into Nanhai. In 757, the Tang administration renamed the county Dongguan, and moved its seat to what is now Dongguan city, although a military garrison remained.