War builds civilisations

Computer modelling suggests that competition between societies, in the form of warfare, drives the evolution of complex societies 

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What the researchers did was to map Europe, Asia and north Africa into 100km squares, each of which had scores for military technology – in the first instance horses but later stirrups, bows and arrows, and so forth – agriculture and ultrasocial traits. Every turn of the simulation represented 100 years, and in each turn there was a chance that agricultural areas would unite and an ultrasocial trait would spread. Military technology also diffused from the nomads, so that an agricultural region was vulnerable not just to the pastoralists of the steppe but to neighbouring cultures that had learned to combine the use of horses or weapons with agriculture. 

When this simulation was run over 7,000 years, the results were eerily close to what actually happened. "Ultrasocial" societies – civilisations – emerged and spread in the same places and at about the same times as happened in real history. The determining factor was the spread of military technology, and the demands that resisting it and wielding it placed on social organisation.

Source: The Guardian

And to think everyone told me those computer strategy games were a waste of time...