Along with migration and drought, another significant development in the centuries around 1200 B.C.E. was the spread of iron tools and iron technology. Iron smelting was developed independently in several different places, including western Africa in what is now Nigeria, Anatolia (modern Turkey), and most likely India. In Anatolia, the earliest smelted weapon has been dated to about 2500 B.C.E., but there may have been some smelting earlier. Most of the iron produced was too brittle to be of much use until about 1100 B.C.E., however, when techniques improved and iron weapons gradually became stronger and cheaper than their bronze counterparts. Thus, in the schema of dividing history into periods according to the main material out of which tools are made (see Chapter 1), the Iron Age began in about 1100 B.C.E. Iron weapons became important items of trade around the Mediterranean and throughout the Tigris and Euphrates Valleys, and the technology for making them traveled as well. From Anatolia, iron objects were traded west into Greece and central Europe, and north into western Asia. By 500 B.C.E., knowledge of smelting had traveled these routes as well.

Ironworkers continued to experiment and improve their products. Near Eastern ironworkers discovered that if the relatively brittle wrought iron objects were placed on a bed of burning charcoal and then cooled quickly, the outer layer would form into a layer of much harder material, steel. Goods made of cast or wrought iron were usually traded locally, but fine sword and knife blades of steel traveled long distances, and the knowledge of how to make them followed. Because it was fairly plentiful and relatively cheap when compared with bronze, iron has been called the “democratic metal.” The transition from bronze to iron happened over many centuries, but iron (and even more so, steel) would be an important factor in history from this point on.