The Khan's early years were devoted to the very difficult and dangerous task of unifying the undisciplined series of small Mongol tribes into a homogeneous group. The unification became the finest and most disciplined army in the world at that time.

Genghis Khan's cavalry were the undisputed masters of the horse and bow. The sounds of Mongolian battle horns on the doorsteps of Europe and the Middle East struck fear into the hearts of the warriors who faced them. Few armies were ever able to match the skill in mobility and ferocity of the Khan's cavalry.

At the time of his death in 1227, Genghis Khan was continuing his conquest and assimilation of China into his Mongol Empire, a task completed by his grandon Kublai Khan.