During the 1200s, the western powers underwent a time of division and intrigue. Various factors contributed to the weakened state of the western civilizations, however the greatest of these was likely the invasion of the Golden Hoard. Genghis Khan led the Mongolian armies from the east west across Asia and Eastern Europe. They pillaged and burned as they went. The Mongolian Empire was among the largest empires in history.
They owed their success in at least some part to their bows and the skilled archers who used them.
What makes a Mongolian bow special is that it is designed with birch wood, bone, and sinew in order to take the best properties of the three and combine them into a single effective piece. The recurve design gives the bow power in a shorter frame than a longbow would have. And the size of these bows means that they could be fired from horseback effectively. This allowed the Mongols to employ Parthian tactics (they would ride away from pursuit, firing arrows back at their foes). This also allowed the Golden Hordes to avoid most direct engagements. They could quickly move away from armed enemies and pick them off skirmish style.
While there is a great deal of myth surrounding the Mongols and their weapons, there is some question as to how realistic even some modern articles are about the capabilities of the Mongolian bows.
For instance, some authors claim that the bows had well over a hundred pound draw weight and could fire arrows nearly a quarter of a mile with accuracy. However, modern archers do not use wooden arrows with bows of such high draw weights because the forces involve cause the arrows to flex and shatter, often injuring the archer when they do.
There is also a competitive tradition among scholars of archery to choose favorites between longbows and Mongolian bows and to argue that one is superior to the other. This discussion is usually heated, and both sides make apparently outlandish claims. This could be brought about because of the old stories which surround both the old British and old Mongol cultures. Western examples are familiar and come to mind: Robin Hood and his Merry Men, as opposed to the riders of the Golden Horde.
Both cultures used archery and bowyery to great effect in establishing themselves as strong world powers.