Why did Qin Shihuang send 500,000 Qin Jun to Lingnan?

After the extinction of Daqin, Zhao Tuo, who was in Lingnan, took out the testamentary edict of Qin Shihuang, which read: In any case, 500,000 Qin Jun must be stationed in Lingnan for generations and cannot withdraw its troops.

This arrangement of Qin Shihuang directly led to the gap of domestic power. After the Chen Sheng and Guangwu Uprising, insurgents from all over the country responded in succession. At this time, Zhang Han, the general who mastered the Korean military power, had to urgently organize 700,000 prisoners of Lishan to form an army to suppress it. But the army composed of prisoners is just a mob, and there are heroes like Xiang Yu in the uprising army, which can't stop the uprising army from invading Xianyang, and the tragedy of Qin Ershi's death is inevitable.

Where are all the mighty teachers of Daqin? After Qin Shihuang unified the six countries, he thought that the country was stable and no one could shake it, but there were still hidden dangers in the frontier, so he sent Meng Tian to lead 300 thousand troops to the northern border to prevent the Huns from invading; Life Zhao Tuo rate of 500000 stationed in lingnan. The order in the testamentary edict is that Zhao Tuo and 500,000 Qin Jun will be stationed here from generation to generation, and no matter what happens in the Central Plains, they are not allowed to leave.

So when the rebels joined forces, the main force of Qin was at the forefront and could not come back to rescue. Taking this opportunity, Zhao Tuo did two things at that time. One is to kill all the officials appointed by the Qin Dynasty in Lingnan and replace them with his cronies. The second is to block all northbound passages and cut off contact with the Central Plains. Zhao Tuo's heart is very clear, he is to mercenaries self-respect.

Zhao Tuo cut off contact with the State of Qin, became king in the land of barbarians, established Nanyue State, and became the king of Nanyue himself. This dynasty lasted for more than 80 years and was finally annexed by the Han Dynasty.