Genghis Khan was born in what is now Mongolia circa 1167 into the Bjorjin Clan of the Mongol tribe under the name Temujin. This was one of about half a dozen tribes in this area of steppe, some of the other notable ones being the Tartars, Ungirrads, Merkids, Kereyids and Naimans They were groups of nomadic horsemen, famed for their fearless and quarrelsome nature.
In previous times, hordes from this area had captured kingdoms in China and created their own dynastys. However, each of these were Chinificated, and instead of Mongol influence extending to China, the reverse occured.
Many of Genghis' ancestors had a record of being leaders of both his clan and the tribe, and his father, Yesugei Bat-atur, was the ruler of the clan. However, he became involved in the warfare between the Chinese-backed Tartars and the Mongols, and when Temujin was 9, a group of Tartars poisoned Yesugei. Left fatherless, Genghis and his family were forced to flee his Clan when the rival Tayichi'ud Clan incited them against him. He spent his formative years living rough, and was several times captured by other Mongols and held to ransom, escaping each time. Aged 16, he married an Ungirrad girl, Borte. Soon after, she was captured and raped by Merkid raiders, and found to be pregnant. It was unknown whether Genghis or an anonymous Merkid tribesman was the father of her first son, Jochi.
She later bore him three other sons, Chagadai, Ogedei, and Tolui.
Genghis spent the next few years in alliance with the Christian leader of the Kereyid tribe, To'oril. Together they virtually annihilated the Tartars, and Genghis acquired a following composed of men from almost every Mongoloid tribe. However, their friendship later turned sour, and Genghis killed To'oril and sacked his camp.
He had meanwhile embarked on the road to unifying the fiercely divided tribes. Unfortunately, his childhood friend, Jamukha, assembled a coalition aiming to stop him achieving this, and obtaining power over all the tribes.
After around a decade, despite several reverses, he finally defeated his last opponents, and Jamukha commited suicide.
The year was 1206, and Temujin was around 40, approaching old age for a Mongol of that era. However, taking the title Genghis Khan, he lived for twenty more years, by his death ruling an empire stretching from southern Siberia in the north to modern-day Afghanistan and Iran in the west, to northern China in the south-east.
He waged war against the Chinese Chin and Hsia-Hsia empires and the Kwhazarahm Shah empire of eastern Persia, and was responsible for millions of deaths.
He also completely reorganised the workings of the Mongol state, encouraging hierachy and drilling his army of horse archers until enemy forces frequently overestimated their size seven-fold.
When he died in 1227, he left the reins of the empire and Northern China to his son Ogedei, Eastern China and Persia to Chagadai, who was also the founder of the Mongol legal code, the Mongol heartland to Tolui, and to the sons of his recently deceased child Jochi he left the as yet unconquered land of Central Asia and European Russia
His empire remained nomadic, and ruled the land merely by raiding it occasionally. In this, its natural function, his army was probably the most effective ever created.
His life and some of the mythology surrounding it was written in 'The Secret History of the Mongols', which he himself commisioned, and which required the creation of a Mongol alphabet
Sources used: Storm from the East by Robert Marshall (published by BBC books)
The Secret History of the Mongols
In Search of Genghis Khan by Tim Severin (Hutchinson)