The Mongols are not always incorporated into the narrative of Western Civilization, because despite the enormous breadth of their empire under Genghis (also Anglicized as Chingis) Khan and his descendants, most of the territories held by the Mongols were in Asia. The Mongols, however, are entirely relevant to the history of Western Civilization, both because they devastated the kingdoms of the Middle East at the time and because they ultimately set the stage for the history of early-modern Russia.
The Mongols and the Turks are related peoples from Central Asia going back to prehistory. They were nomads and herders with very strong traditions of horse riding, archery, and warfare. In general, the Turks lived in the western steppes (steppe is the term for the enormous grasslands of Central Asia) and the Mongols in the eastern steppes, with the Turks threatening the civilizations of the Middle East and Eastern Europe and the Mongols threatening China. A specific group of Turks, the Seljuks, had already taken over much of the Middle East by the eleventh century, and over the next two hundred years they deprived the Byzantine Empire of its remaining holdings outside of Constantinople and its immediate surroundings.
Meanwhile, in 1206 the Mongols elected a leader named Temujin (b. 1167) “Khan,” which simply means “warlord.” The election was the culmination of years of battles and struggles between Temujin and various rival clan leaders. By the time he united the Mongols under his rule, he had already overcome numerous setbacks and betrayals, described years later in a major history commissioned by the Mongol rulers, the Secret History of the Mongols. After his election as Khan, he set his sites on the lands beyond Mongolia and eventually became known as Genghis Khan, meaning “Great Khan.” Genghis Khan united both the Mongols and various Turkish clans, then launched the single most successful campaign of empire-building in world history.
Temujin personally oversaw the beginning of the expansion of the “Mongol Horde” across all of Central Asia as far as the borders of Russia and China. Over the following decades, Mongol armies conquered all of Central Asia itself, Persia (in 1221), northern China (in 1234), Russia (in 1241), the Abbasid Caliphate (in 1258), and southern China (in 1279). Importantly, most of these conquests occurred under Temujin’s sons and grandsons (he died in 1227), demonstrating that Mongol military prowess was not dependent on Temujin’s personal genius. Ultimately, the Mongol empires (a series of “Khanates” divided between the sons and grandsons of Temujin) stretched from Hungary to Anatolia and from Siberia to the South China Sea.
Mongol military discipline was extraordinary by pre-modern standards. Starting with Temujin himself, all Mongols were beholden to a code of conduct and laws called the Yasa (historians debate whether or not the Yasa was a codified set of laws or just a set of traditions). They were divided into units divisible by ten, from hundred-man companies to ten-thousand-man armies called Tumen. Since clan divisions had always undermined Mongol unity in the past, Temujin deliberately placed members of a given clan in different Tumen to water-down clan loyalty and encourage his warriors to think of themselves as part of something greater than their clans.
Mongols had strict regulations for order of march, guard duty, and maintenance of equipment. All men were expected to serve in the armies, and the Mongols quickly and efficiently plundered the areas they conquered to supply their troops. Mongols trained relentlessly; during the brief periods of peace they took part in great hunts of animals which were then critiqued by their commanders. Each warrior had several horses, all trained to respond to voice commands, and in battle Mongol armies were coordinated by signal flags.
The Mongols also made extensive use of spies and intelligence to gather information about areas they planned to attack, interviewing merchants and travelers before they arrived. They were noteworthy for being willing to change their tactics to suit the needs of a campaign, using siege warfare, terror tactics, even biological warfare (flinging plague-ridden corpses over city walls) as necessary. Once the Mongols had conquered a given territory, they would deport and use soldiers and engineers from the conquered peoples against new targets: Persian siege engineers were used to help the conquest of China, and later, Chinese officials were used to help extract taxes from what was left of Persia.
The Mongol horde often devastated the lands it conquered. Some, like the Central Asian kingdom of Khwarizm, were so devastated that the areas it encompassed never fully recovered. Temujin himself believed that civilization was a threat that might soften his men, so he had whole cities systematically exterminated; in some of their invasions the Mongols practiced a medieval form of what we might justifiably call genocide. Fortunately for the areas conquered by the Mongols, however, under Temujin’s sons and grandsons this policy of destruction gave way to one of (often still vicious) economic exploitation and political dominance.