Why Btonze Age?

[The Grand Nudger]

It pretty much boils down to weaponry. As is often the case with humanity. Iron gave you a literal edge over bronze. So Iron had an advantage. Not only in war, but also in terms of agriculture.

Yeah but it is a bit more complicated than that.  The Greek hoplites, who were sine qua non as a military force wore bronze armor and had bronze spear points until fairly late in the hoplite period when they switched to a, believe it or not, laminate armor!  Even the earliest hoplite swords, the xiphos were made of bronze.  I suppose much of it depended on what was available.  You needed copper and tin for bronze.  For sea-faring trading states like Athens, Phoenicia or Carthage obtaining the raw materials was fairly easy.  For states like Sparta it was probably a little more difficult.  Nonetheless, they managed.

I suspect the one thing that led to iron's eventual preference was that it was much more common and thus cheaper to produce.  I don't know that it produced "better" weapons but it sure as shit could produce more weapons.

Laminate can be pretty damn strong, it's laminate that makes a modern mechanical recurve work.  

However, more was the selling point.  The casting process for bronze had overlap with the hammering process for iron, and a short iron could slice bronze studded like butter, allowing for close range "testudo" formations with cheaper, shorter swords that turned phalanxes into meat.  Cheaper being important.   Predictably, "bronze god" was powerless against the economy and strength of iron regardless of the strength of his laminate, thus Judges 1:19 and the rise of cultures which occupied iron rich lands.

Perhaps more important, militarily, than all of that, was irons ability to form a heavy moldboard plow that could cut the sod of europe (and truly cultivate medi soil). If I had a few ounces of iron I'd beat it into a ploughshare rather than sword, because I could pay for, and feed, more soldiers off that plow than I could from a long iron knife.