Bronze- versus iron-based economics changed the kind of societies that could exist

19.11, Monday 13 Sep 2021

In the long run, is economics the mould that shapes society?

I’ve been learning about the Late Bronze Age collapse recently (that’s the Wikipedia page).

A period of a few decades between c. 1200 and 1150 BCE saw the cultural collapse of the Mycenaean kingdoms, of the Kassites in Babylonia, of the Hittite Empire in Anatolia and the Levant, and the New Kingdom of Egypt; the destruction of Ugarit and the Amorite states in the Levant, the fragmentation of the Luwian states of western Anatolia, and a period of chaos in Canaan.

These civilisations all interacted with one another, and had a carefully negotiated co-existence – the first international diplomatic system known to us – discovered via a cache of clay tablets found in Egypt called the Amarna letters.

After collapse: trade and diplomacy shrunk; literacy and quality of life decreased.

What caused it? Candidate explanations include:

  • volcanos, droughts, etc
  • invasions by the mysterious Sea Peoples
  • new military tactics
  • and more.

But those named ones feel like stressors not causes. And others candidates (political collapse; class struggle) sound again not like causes but consequences.

So my favourite candidate is the shift from bronze to iron.

Here’s an episode of In Our Time on The Bronze Age Collapse (June 2016). I learnt a bunch.

For example, about bronze itself:

  • Bronze was vital for power: institutions and armies. It was used for chisels to cut stone for building programmes; it was used for weapons (in particular is allowed swords) to wield military power.
  • But bronze is rare, being made from copper and tin which are not found everywhere: It is plentiful enough that it’s widely available, and rare enough to have to capture those [trade] routes and so on. (Even the knowledge of how to create the bronze alloy is rare.)

Iron was emerging around the time of the Late Bronze Age collapse, although it wasn’t common until the 7th century BC (400 years later).

But iron undermines bronze-based power structures. Again from that episode:

One could argue that iron, which of course unlike copper and tin is almost everywhere, so is readily accessible - so you don’t need to build long-distance trade routes to find it and so on - you can take a broad view that that it undermines the ability to monopolise long-distance trade. Therefore smaller entities can get involved.

When states arose to replace those the collapse, they looked different: new people organised politically in a different way. The new states were smaller and more numerous than the older, grander palace kingdoms.


Here’s the story I tell myself about bronze:

It sounds to me like bronze is intrinsically connected to the foundations of how power is established and maintained.

Over time, bronze requires and allows for great concentrations of wealth, and that’s why we see this small number of incredibly wealthy, grand palace kingdoms. Their prestige, after centuries, relies on highly efficient extraction of wealth from their networks.

But then comes iron. Iron is an evenly distributed technology (as a material, and knowledge of how to work with it). It can’t be monopolised.

Even in iron’s infancy, it allows for a kind of peer-to-peer trade and wealth to arise.

And that destabilises the status quo. Which is turns out has become brittle.

I think of stressor events on a system a bit like shaking up a box full of oddly-shaped rocks. During the shaking, the box “settles” towards its low energy state; the rocks end up more closely packed. In previous centuries, stressor events have shaken up these civilisations, and they’ve “settled” into palace kingdoms.

But now the status quo, the low energy state, has altered. Iron is present. So the stressor events (climate change, invasions) “settle” the system towards a new status quo, one which doesn’t involve the palace kingdoms.

And so they collapse.


We’ve seen this story before!

Around 13,000 BCE, Europe warmed out of its Ice Age, and mobile hunter-gatherers settled into villages. Long-distance trade routes emerged around seashell trade, used to display wealth – wealth disparity and elites emerged around that trade.

But a thousand years later, the Ice Age re-emerged (temporarily). The villages vanished… and the elites too:

Wealth and power had evidently been dependent on sedentary village life. This provided the elite with the opportunity to control the trade that brought seashells and other items to the villages. A return to mobile lifestyles swept away the power base and society became egalitarian once again.

I wrote this up last year: Some rambling thoughts about the stuttering end of the last ice age and what lockdown means (April 2020).

So these are two stories of economics providing the attractor to which the chaotic system of society gradually drifts.


The picture in my head is that certain kinds of material scarcity allow for the monopolisation of exchange, and that allows for the hoarding of wealth and the creation of elites, where the elite system becomes self-reinforcing… and increasingly efficiently but ultimately brittle – until the material scarcity itself changes. Then we see collapse.

HUGE CAVEAT: this is all a wild guess based on not-even-adequate reading about stuff that happened and a strong dose of systems thinking. I find all this fascinating.

If I could go back and do it all again, I would probably study history.


And if bronze is technology which can be monopolised, and iron is technology which is evenly distributed, does the story of the Late Bronze Age Collapse hold lessons for centralised versus decentralised technologies in modern times?

Directly: I’m thinking of finance, and data.

Indirectly: I’m thinking of social communication. Do bottlenecks in the “trade routes” of communication (that is, social media) necessarily lead to wealth disparities in the equivalent currency – which in this case would be social capital? That is, the more efficient our global broadcast systems, the more extreme celebrities we create?

If you enjoyed this post, please consider sharing it by email or on social media. Here’s the link. Thanks, —Matt.

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