In 215 BC , Qin Shi Huangdi ordered Request General Meng Tian to set out Military_operation against the Xiongnu tribes in the Ordos region , and establish Building a frontier region at the loop of the Yellow River .

As a result of the northward expansion Expansion , the threat Warning that the Qin empire posed Causation to the Xiongnu ultimately led to Causation the reorganization of the many different Xiongnu tribes into a confederacy .

Crown Prince Fusu and General Meng Tian were stationed Placing at a garrison in Suide and soon began Process_start with the construction of the walled defenses Defending , which would be connected Connect with the old walls from the Qin , Yan , and Zhao states .

The Qin walls ran from Liaodong to Lintao , thus enclosing the conquered Conquering Ordos region .

Military expansion Expansion to the south began Process_start under the previous Qin dynasty and continued during the Han era .

The Chu–Han Contention Competition ( 206–202 BC ) was an interregnum between the Qin dynasty and the Han dynasty in Chinese history .

Following the collapse Process_end of the Qin dynasty in 206 BC , Xiang Yu split Destroying the former Qin Empire into the Eighteen Kingdoms .

Following the collapse Process_end of the Qin dynasty in 206 BC , Xiang Yu split Destroying the former Qin Empire into the Eighteen Kingdoms .