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 is the most common element in the earth, but most iron found on or near the earth’s surface occurs in the form of ore, which must be smelted to extract the metal. This is also true of the copper and tin that are used to make bronze, but these can be smelted at much lower temperatures than iron. As artisans perfected bronze metalworking techniques, they also experimented with iron. They developed a long and difficult process for smelting iron, using charcoal and a bellows (which raised the temperature of the fire significantly) to extract the iron from the ore. This procedure was performed in an enclosed furnace, and the process was repeated a number of times as the ore was transformed into wrought iron, which could be hammered into shapes.

Exactly where and when the first smelted iron was produced is a matter of debate — many regions would like this honor — but it happened 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, 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. Iron appears to have been adopted more slowly in Egypt than in other parts of the Near East, so bronze remained important longer there. 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. Somewhere in the Near East — again the exact location is disputed — 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.