Steel was known in antiquity, and may have been produced by managing the bloomery so that the bloom contained carbon.[9] Some of the first steel comes from East Africa, dating back to 1400 BC.[10] In the 4th century BC steel weapons like the Falcata were produced in the Iberian Peninsula, while Noric steel was used by the Roman military. The Chinese of the Warring States (403–221 BC) had quench-hardened steel,[11] while Chinese of the Han Dynasty (202 BC – 220 AD) created steel by melting together wrought iron with cast iron, gaining an ultimate product of a carbon-intermediate—steel by the 1st century AD
Source: http://en.wikipedia.org/wiki/Steel