Most of the nomadic peoples in ancient history, when they had a certain degree of strength, would launch large-scale military expansion operations. The most typical of these is genghis Khan, the "generation of heavenly pride", in the thirteenth and fifteenth centuries, the period of nomadic splendor, the Mongol iron hooves spread throughout Eurasia, countless peoples have submitted to them.
The reason for this phenomenon can be summed up in two words, and the main reason why the ancient nomadic peoples, represented by Genghis Khan, frequently launched military expansion operations was for the purpose of "plundering".
Because the ancient nomads lived a nomadic life of chasing water and grass, the kingdoms they established were different from the kingdoms established by the farming peoples, and the kingdoms established by the nomads generally had a weak economic foundation, which was also related to the environment on the steppe and the way of life of the nomads, but their "martial virtues" were more abundant.
In the American drama "Game of Thrones", the tribal language of the Iron Folk Greyjoy family is "stronger than bitter farming". This sentence can also reflect the mentality of the ancient nomadic army like to expand.
The weakness of the economic base is that the "materials" of the ancient nomads are very scarce, and even the iron pot has to be exchanged from the merchants of the farming peoples, and when the nomadic kingdom reaches a certain strength, it must promote the economy by waging war.
Between the thirteenth and seventeenth centuries, the Tatars and Nogais living in the steppes of Eastern Europe liked to periodically raid the gathering places of farming peoples. When they arrived in a village or market town, they would rob the locals of their wealth, and when the wealth was looted, they would rob the local children and young adults, and then sell these plundered people as slaves to the Ottoman Empire.
Scholars have called this action of the Tatars and Nogais "steppe economy." The Tatars and Nogai were only petty battles, and when a nomadic kingdom began to grow stronger, their plunder would not be limited to market towns and villages, but to conquered entire kingdoms or peoples.
If a nomadic people wanted to be strong, they had to unify the entire tribe, such as Genghis Khan, who had unified most of the tribes of Mongolia before he expanded abroad. When their own tribes are unified, civil war is meaningless, so they must wage foreign wars.
After Genghis Khan and his Mongols became powerful, they began to wage wars non-stop, and in addition to the wars against the Western Xia and Jin Dynasties, the largest was the war against the Khwarazm Kingdom in Central Asia. Genghis Khan's westward expedition to Huarazm paved the way for the rise of the Mongols and their continued westward advance.
If you look at the history books of Genghis Khan's western expedition to Huarazm, you can find that when the Mongols captured a city, they would loot the wealth in the city, and this wealth was very important to the Mongols, wealth could stabilize the military, and could obtain excellent armor and weapons, as well as siege equipment that the Mongols needed very much.
In addition to wealth, nomadic armies that wage war plunder "talent." Everyone knows that the Mongol army liked to slaughter cities when they expanded, but they did not all slaughter. Due to the small number of ancient Mongols, they liked to plunder young adults in conquered lands as "cannon fodder" when they expanded abroad, so as to reduce the casualties of the Mongol army.
Craftsmen with craftsmen, the Mongol army generally did not slaughter, because they can make combat and daily necessities for the Mongols, such as Genghis Khan in the Western Expedition to Huarazm, captured a lot of craftsmen to serve the Mongol army.
Learned nobles or commoners, the Mongol army generally did not massacre, as long as they were willing to be loyal to the Mongols, the Mongol nobles would give them good treatment, because they could help the Mongolian nobles to manage the country, for example, after the Mongol conquest of the Jin Dynasty and the Southern Song Dynasty, there were many Central Asians serving in the newly conquered lands.
Wealth and talent are the necessary guarantees for a country to be strong, which is also the main reason why the nomadic armies continue to wage wars, and they exchange wealth and talents by force to ensure that their kingdoms continue to grow stronger.
Reference: Prairie Empire