Will Durant says they were "half-mongol, half-European, ferocious bearded gaints who lived in wagons and ... fought to live and lived to fight... destroying and killing everything in their path ... were suddenly decimated by a mysterious disease and were finally overcome by the Medes and driven back to their northern haunts." William Durant - Our Oriental Heritage That sounds a lot like legend. Who were these people? Did they survive in any way to present-day?
We don't very much about the scythians but they are thought to have been nomadic tribes of mostly eastern-iranians who inhabited the Eurasian steppes, from central asia to modern day Ukraine. They lived in this area from about 900 BC to 400 AD.
They were among the first people to effectively use mounted warfare, and may have spread the use of cavalry to Europe. They would often sweep in on horseback, attack and raid the country-side, and quickly retreat back to their lands in the steppes. This gave the scythian status as legendary warriors of myth, and many lived in fear of them.
Eventually environmental changes and invasions by other people displaced the scythians, some went south into persian lands and settled what is today Sakastan, or land of the scythians. Another group formed the Alani, who invaded Rome and formed Kingdoms in modern day France, Spain and Tunis. Eventually these people settled in the Caucausus and remain there to this day as the Ossetians, who still speak an eastern-iranian language descented from Scythian. Another group, the Pashtuns, also speak an eastern iranian language and live in what was Scythian lands.
Many other people have claimed Scythian descent, such as the French, the Gallic, the Celts, the British, the Croats, the Polish, the Russians and the Turks just to name a few.