Preamble: when we think about economic and political structures, we generally tend to think of them as bound within national borders. But as the world changes, this too may change. In almost all countries, we already talk about the split between the rural and urban votes. And with growing urbanization, that separation is likely to grow rather than recede. In our life-times, we may well see the emergence of ‘new’ countries: in the form of city-states.

Here is a map of South Africa’s average taxable income, broken down by province:

Given that, it should come as no surprise that the metropolitan municipalities of Gauteng (and Johannesburg in particular) make the highest contribution to the country’s GDP.

But the land map here is also misleading. Because ‘nationhood’ is a belief-system that exists within the minds of a people. So when we talk about ‘countries’, we should probably be mapping that belief-system of minds rather than a geographic land allocation.

So here is a population cartogram:

Mapping Population, and the rise of the City-States

Worldmapper.org has a team of cartographers that have spent a stack of time using population census data to build country-specific maps showing the distribution of population within a country’s borders.

And immediately, we see urbanisation.

And it’s changing the way that we do things.

The rise of global mayors

There was an interview that I listened to some time ago (on the Freakonomics podcast) with Boris Johnson, the former mayor of London.

At the time, Boris was about to turn-coat on David Cameron, and come out in favour of Brexit. That move was widely seen as his gamble for the seat of Prime Minister. I remember thinking how bizarre it was that Boris was considered a real candidate for Prime Minister of the UK. He was “just” the mayor of London. It just seemed like too rapid a promotion. Almost as though you shouldn’t be going from running a city to running a country, because he wasn’t even a member of parliament, and that’s too big a leap. Or something.

But then he started talking about global mayors, and the influence that their cities have, and the role that they play in them.

And I changed my mind.

Some City Numbers, according to McKinsey in 2014

As of 2010, half the world’s population lives in cities.

Cities account for 80% of the world’s GDP.

According to the UN, by 2020, two thirds of the world’s population will live in cities.

Already, the top 100 cities accounted for 38% of global GDP in 2007.

Also, this astonishing line: