It took me twenty years to dig out the stories of the successors of Genghis Khan.

His was the largest land-based empire in world history. He left a last will and testament. He named an heir. The conquests were spectacular military feats, ruthless but not motivated by bloodlust. What happened to the empire after The Conqueror died?

I wanted to know. I became a detective, an archaeologist digging out the story.

What happened was earth-shattering. The Mongol Army was the lone superpower of the Middle Ages, superbly commanded, trained and equipped.

The Supreme Khan believed he was destined to govern all peoples, that he had the blessing of the Eternal Blue Sky, the deity of the shamans.

His career consisted of breaking up the great empires of the past and laying the foundations of modern times.

He was misunderstood and maligned. He was called bloodthirsty, which he was not. He was called a barbarian, but modern scholarship has rescued his reputation. He was a nomad, the khan of hundreds of thousands of clans, the proud owner of herds, who lived in a tent and pursued the free open life of the pastoralists. But then, the medieval world was composed of islands of civilization, or settled agriculturalists, surrounded by nomads, or pastoralists. The ranchers and the farmers, to put it in terms of the American West.

This was the first era of global history, the beginning of the modern world. The roads opened. Peace reigned. Global trade commenced. Fortunes were made. Cultures intermingled. Cultures influenced each other across the world.

This was his legacy. His reign brought peace for one hundred years. His law protected trade. Europe got into the international trade with Asia. The world order changed. The Arab/​Muslim dominance of the world's trade and banking systems came to an end when the Mongols entered the Middle East. This brought about the rise of the West.

This was like an earthquake. The plates of the world order shifted. Europe had been a backwater after the fall of the Roman Empire. After the invasion of the barbarians. Even the local markets had collapsed.

All that changed with the coming of the Mongol Army, the army that guaranteed the safety of the caravan trade. The fortunes made in the trade between China and Europe paid for science and technology. Science and technology gave Europe the edge. The rise of the West was built on science and technology.

Europe was in the infancy of capitalism, but through its shipbuilding and navigational instruments rose to dominate the world's oceans. Europeans mastered open ocean sailing. The vessels were bigger, they precision instruments were better for navigation, they had big cannon on board. The China trade ushered in the Age of Exploration.

Before the mastery of the oceans was the world of the camel caravan, overland trade, and a maritime trade that did not include open ocean sailing. The Maritime Silk Road was a coastal trade.

Trade during the era of the Pax Mongolica was lively: Europe was mad for spices, textiles, porcelains and tea. This was the world of the Silk Road, Marco Polo's world. The trading houses of Genoa and Venice had emporia on the Caspian Sea. There they traded for the goods of China, sent them via the ports of the Black Sea to Constantinople, the capital of the Eastern Roman Empire, and from there the goods went by ship to Europe and North Africa.

The Mongol world was not simply about war. The Mongol world was about trade.

Marco Polo, a merchant of Venice, rose from his status as a commoner and became an official at the court of Khubilai Khan. He was the greatest travel writer of all time. He left such a vivid account of the amazing things that he witnessed at the court of the Khan that when he returned to Venice, he was called, Marco Miliones, the man of a million tales. In other words, he was branded a liar. No one in Venice could believe that the Chinese had paper money, printing, and heated baths.

Marco's father and uncle had opened a branch of their Venetian emporium in the trading city of Soldaia on the Caspian Sea. This was a European outpost in Asia where European merchants could eliminate some middlemen and increase their profits. From the Caspian, the goods went to Black Sea ports and Constantinople, and from there to Europe and North Africa.

Like an archaeologist, my method was discovering fragments of stories in the best sources and piecing them together like old ceramics. Piecing the fragments together, weaving together the stories, the tale emerged.

The stories did not end with the death of Genghis Khan. The sons and grandsons and the daughters-in-law carried the tale for generations. For example, there was a battle for the throne at the top of the Mongol world, and one of the khans won. He was the best of the rulers after the founder, the military genius known as The Conqueror.

This grandson was a military hero. He was a miser. He had a philosophical turn of mind, and he knew how to use the resources of empire to fill up the treasury that his two drunken predecessors had emptied.

Europe was a backwater. It was poor, still recovering from the fall of the Roman Empire. He decided not to wage war in Europe. He focused on China and Persia, two rich civilizations. He created a battle plan for the conquest of the Middle East during the time of the Crusades. His general brought down the caliphate at Baghdad and the Order of the Assassins in Iran. In so doing, he rewrote global history.

This excavation, digging out the pieces, took a vast amount of research. Twenty years in time, but I was like Captain Ahab in search of the white whale. The story was my white whale and I was rewarded. The world of Genghis Khan opened up the roads from East to West. His Code of Laws kept the peace. The world of the European trader in Asia, Marco Polo's world, came to life.

Each of my volumes is a portrait of a principal character. The stories concern the heroes of their time: Chancellor Yeh-lu, the man who saved Chinese civilization. Princess Sorghagtani, the most remarkable woman of the age. Batu, the grandson of Genghis Khan who conquered Russia and Eastern Europe. Hulegu, the Khan who laid siege to Baghdad, a man still remembered in Friday prayers today because he brought down the twin power centers of the Muslims in the Middle East.

The chroniclers and historians who left the written record were enemies of the Mongol Empire. Men of the book told the tale. They were biased. The Mongols had only had a written language for twenty years at the time of the conquests. Their enemies left the written record. Genghis Khan had the worst press of any military leader in history. The conquests were vast, and the tales told in so many languages that no one could master all of them in a lifetime. The generation of scholars who came of age after World War II had the benefit of not having to stick to their own specialized regions, because so many primary sources had come into English.

As to the historians and chroniclers, of many nationalities and faiths, their states had been conquered by the the greatest fighting force in the medieval world. In many cases, the conquest came like a bolt out of the blue, a storm from the East. How to explain it? The chroniclers routinely exaggerated the size of the forces. They misunderstood the method of waging war. The Russians called the Mongols by the name Tartars, from the Latin for hell.

Why did Genghis Khan recruit a Chinese chancellor after the conquest of North China? He needed to know how to govern the civilized world and he barely understood it. For him the only life was the free open life of the steppes. The story of Yeh-lu Chu-tsai is the story of civilization versus barbarism. The Great Khan admired educated men, and he wanted the knowledge of his chancellor. He got the civilizing influence. In his public life, Yeh-lu was a Confucian because he believed that Confucianism was the best philosophy for the ordering of the state. In his private life, Yeh-lu was a Buddhist, and convinced the Great Khan that the slaughter only fomented the epidemics of battlefield diseases. Yeh-lu was one man, but his knowledge was a moral force.

The Mongol Army was disciplined, trained to a high standard of perfection in cavalry warfare. The Supreme Khan was an innovator in cavalry technique. He developed exercises and tactics based on the Grand Hunt, the greatest spectacle in Asia. The men fought as units, timed and in formations, connected by signal flags, over great distances.

They fought in formations designed to defeat the enemy line. They adapted to terrain. The opposing generals had never seen anything like it. They wore heavy armor and they fought, not as units, but as individuals.

The armies of the civilized world were no match for nomad cavalry. These were men born to the horse. Their fellow nomads in Central Asia were the men who invented the saddle and the stirrup.

The Supreme Khan developed the art of siege warfare, once he encountered wall cities in China. The Mongol generals brought siege engines from China, and then when they conquered the Muslim armies of the Shah of Central Asia, they incorporated the siege engines of the Muslim world.

It is said that the German general Rommel based his tank warfare in North Africa in World War II on the battle tactics of Genghis Khan, using tank divisions as the Khan used cavalry.

Those who leave the written record, the historical record, have an advantage. They tell the tale. The men of the book in the lands conquered by the Mongol Army had their revenge. Chinese, Russian, Armenian, Persian, Arab, Japanese, Hungarian--these chroniclers left the written record, the sources that gave Genghis Khan and his successors, the Mongol Empire, the worst press in history. It has taken time for the post World War II generations of scholars to paint a more balanced portrait. I belong to those generations.

Genghis Khan had a reputation for bloodthirstiness, The victories were chalked up to the idea that vast numbers of men, the barbarian hordes, slaughtered their way across the world. The hallmark of the Mongol Army was quality, not quantity. The slaughter was the way in which medieval warfare was conducted, by the armies of Christianity and Islam as well as the Mongol Empire.

Their is no masking the dark side of the conquests. The Supreme Khan never left an enemy population behind the advancing front lines of his army. This was for tactical reasons, not for the pleasure of killing. Once he employed a Chinese chancellor, Yeh-lu Chu-tsai, the Chinese influenced the worst of Mongol military practices. He was a physician and he argued that he had to stem the tide of battlefield diseases.

The numbers of troops were inflated and so was the devastation. This is not to make light of the devastation. Thirty years after the conquest of Bukhara, Marco Polo spent two years in a caravanserai in the city because two khans were fighting and commercial traffic was stalled. Even in the space of thirty years, Bukhara was a thriving center of intellectual life and of commerce. Still other places never recovered from the warfare.

The inventor of modern warfare, Genghis Khan introduced the element of psychology into his warfare. He ordered his generals to deliver Orders of Submission. "Submit and be spared. Resist and be plunged into humiliation."

He terrorized those in the direct line of his army as a signal to those in the line beyond. He wanted to be spared the difficulty of waging war. He promised good treatment to those who surrendered. He offered command under Mongol generals to Chinese generals who submitted during the Campaign in North China. He used human shields in his conquest of walled cities.

Think of it. China and Russia were both conquered by the Mongols. Neither were as centralized and authoritarian as they later became. Both of these civilizations were ashamed of their conquest by so-called barbarians. Both produced histories that considered the Mongol period a Dark Age.

This is why I had to excavate the stories: I had to piece together various sources, histories and chronicles, to remedy the silence. The silence was a matter of national pride. What did it say about a civilization that believed in its own superiority if it was conquered by a civilization that it considered "uncivilized"?

The Mongols did for the Chinese what they were unable to do for themselves, namely, put China proper together again. Khubilai Khan, a man born to the horse, took to the sea for his conquest of Southern Song, the battles that reunified China for the first time in 400 years.

Khubilai Khan founded a Chinese dynasty that lasted for a century. His dynasty was called the Yuan. It was a time of innovation in the arts and scientific advancement. He built works of civil engineering, he restored the Grand Canal so that he could ship rice from Southern China to the North. He built a Chinese capital and ruled as a Chinese sage-emperor.

This period saw the birth of new forms in literature, the court drama and the novel. It also saw the invention of a whole new category of painting, horse painting, for the Mongols loved their horses and were great customers for the genre.

Khubilai ascended the Dragon Throne and ruled China as a Chinese emperor in the Confucian mold, a benevolent sage-king. It was said by the Mongol Old Guard that he had gone off the deep end, and became too Chinese. His Chinese-ness was the source of rebellions by the Old Guard who wanted the preservation of Mongol traditions.

The great Russian hero Alexander Nevsky saved Mother Russia from the Teutonic Knights sent by the Pope of the Church of Rome to bring Russia back to the fold of the One True Church. The problem with Russia was not that the Mongols conquered Russia but that they ruled Russia for 250 years.

What did it say about the Russian Orthodox Church if God allowed Russia to be defeated? What did this say about the Chinese imperial system, the Central Country receiving tribute from its neighbors, if the greatest civilization in Asia could be defeated?

This is why I set about digging out truth with a teaspoon. It was not like writing about Henry VIII, where there were twenty volumes of history. There was The Big Silence. The story was never told properly. Even the numbers of the army were exaggerated, to make sense of the victory. Of course the Mongol Army prevailed, went the reasoning. Who could withstand the marauding hordes?

Think of it, dear reader. The Mongol generals were poised to conquer Europe, for Europe was divided, its armies no match for the greatest fighting machine of the time. The Pope and the Holy Roman Emperor were engaged in a power struggle with each other, and could not mount a common defense. The Mongol Army would have done beaten the armies of Europe as they beat the armies of the crowned heads of Eastern Europe. Only the death of Genghis Khan's successor, the Supreme Khan Ogodei saved Europe.

This was the first era of global history. We are living in a new era of global history. If it is true that the past is prologue, then the reader will derive a great benefit from knowing what has gone before. The patterns of trade are just as fascinating as the annals of war.

I have given you the characters, the good, the bad and the ugly. Here are the conquests that both Russia and China buried in their histories, for they did not want to admit that their civilizations were defeated by so-called barbarians.

What you get with the Mongol Empire are wars and romance, victories and defeats.

Read how the great khans came to power and about their private lives. Once you read my forthcoming series, you too may become obsessed. They were a lively bunch and I have uncovered their stories for modern times. Get on your pony and ride.