Many nomad tribes from the Steppes of Central Eurasia have swept down upon the sedentary peoples of Europe and China throughout history. The Mongols used wholesale slaughter to spread terror and encourage enemies to surrender without a fight; Timur the Lame (Tamberlaine) caused pyramids of human heads to be built up so that his name would cause the whole world to tremble. Centuries before, the Scythians hung scalps from their horse's harnesses to terrify the Persians and the Greeks they met. One thing that is very noticeable about all of these Steppe peoples is how similar in so many different ways they were.
Unlike the Mongols, the Scythians came from the western part of the Steppe area and spoke a language very similar to Iranian. Yet their loose trousers, capes and jackets were similar to those worn down the centuries by subsequent tribal groupings. So too were the composite bows they used - although they did have a sharper angle to them, like, so it is said, Cupid's bow. Made from a central wooden stave covered on one side by sinew and the other by bone, the composite bow was a significantly superior weapon to the self or simple bow used in western Europe, which was made from a single piece of wood. Further, the ability that the Scythians had in shooting their bows while manoeuvring their short, mobile horses, was unmatched in Europe. Swooping down upon the enemy, loosing a cloud of arrows and then running away at speed were tactics that defeated enemies for more than a millennium.
The Scythians attacked the Medes and took their territory, bringing them into contact with the Persians. These too were defeated and the Scythian empire was created in largely Persian territory. They came into contact with the Greeks and even sent a few mercenaries to fight alongside the Athenians. Perhaps our best source of invention about the Scythians - apart from archaeology - is Herodotus, who devoted one whole book of his Histories to a description of the people. He noted how hardy they were and how strong - although on the whole he was of the opinion that they were disreputable barbarians with little to show that was worthy of respect.
Along with other nomads, the Scythians had a semi-symbiotic relationship with the settled people in the land surrounding the Steppes. Pure nomadism is not a sustainable way of life - trade or raiding is essential for nomads to obtain the other items they need to survive. Indeed, many nomads actually have pursued some types of agriculture themselves when necessary. From the perspective of the settled peoples, the nomads appeared to be parasitic terror-mongers of no real humanity or value. History is, by and large, written by the settled peoples and, as a result, the reputation of the nomads has been rather poor.
Just as happened with the semi-legendary Cimmerians before them, the Scythians eventually faded away from history when their military ability was overcome. Living by the bow meant that the nomadic Scythians eventually died by, if not the bow, then the sword.