Bread and circuses, canals and monuments

The Romans already knew, that if you want the people to be happy, you have to give them bread and circuses. But what happens when you run out of bread? ‘and circuses’ doesn’t quite have the same ring to it…

I don’t know what the Romans did, but thanks to Melissa del Rosario Rubio-Ramos, Christian Isendahl, and Ola Olsson I now know what the ancient Mayas did.

In a study that combined archaeology, geology, and economics, they looked at 870 dated monuments in 110 classic Mayan cities. The monuments covered the period from 250 CE to 950 CE and are the stand-in for the Roman circuses. They are temples and other places of worship as well as monuments to great military victories. Essentially, and just like circuses in ancient Rome or statues of Kim Yong Un in North Korea, they are symbols of the power and wealth of the regime and a form of entertainment to distract people from other issues. Like not having bread…

So what about the ‘bread’ part? The researchers used rainfall data collected from sediment layers in caves as a proxy for how good harvests were and how much bread there was to go around. Below, you can see the estimated average rainfall and the number of monuments that were constructed.

Rainfall and Maya monument construction

Source: Rubios-Ramos et al. (2024)

If we ignore the early classical period (250-550 CE) when hardly any monuments were built, visual inspection indicates that if there was less rainfall, the Mayas built more monuments. Using additional sources the researchers also found that in periods of less rain, wars became more prevalent.

The latter makes sense, but the former looks stupid. It seems intuitively clear that if you have a starving population because rainfall has declined, one good way to increase the amount of bread per person is to take a bunch of mates and invade a neighbouring city. On the one hand, it reduces the number of mouths to feed at home if some of your mates get killed by the enemy. On the other, if you win the fight, you can plunder the conquered city including its animals and grain reserves. It’s a win-win when you think about it this way.

But what about building more monuments when there is less bread? That seems foolish. Surely, when there is less rainfall, you’d invest in building more canals and water reservoirs which the Mayas were really good at. And with better infrastructure, they’d waste less water and be able to produce more bread with limited resources.

That would be the technocratic solution. But technocrats never get elected, and they are not very popular with the people when they accidentally get into power. Nobody likes a sensible politician.

Instead, the correlation between rainfall and monuments built (once adjusted for wars and other events) is negative as in the chart below.

Rainfall and Maya monument construction

Source: Rubios-Ramos et al. (2024)

So, why are rulers building more monuments when the people starve? It is a form of signalling. It demonstrates to the people that the ruling class is still powerful and they better not revolt against them. If they can afford to build monuments, guess how much money they have left to send a bunch of soldiers your way?

In short, if you follow a policy of bread and circuses and the bread runs low, dial up the circuses to distract people from their empty stomachs. And that still works today. Just ask Kim Yong Un.