In the city of Rome, I think many adults did actually die young, in addition to infant mortality. And they were replaced by imports from the countryside. In fa

In the city of Rome, I think many adults did actually die young, in addition to infant mortality. And they were replaced by imports from the countryside. In fact I think no large city was self-sustaining, perhaps until London, c 1800? Having that many people in proximity simply wasn't healthy. For much the same reason, very few wars before WWI (perhaps none?) had more men killed by the enemy than by disease.