up until the year 1900 the world's cities were massive genetic blackholes. Cities only kept their population up through migration, which explains how Rome shrunk to 30,000 inhabitants by the 7th century.
Today,. we think of cities as places where people come to thrive. Wealth is higher in cities than in small towns and rural areas. Richard Florida tells us that the creative class is to be found in cities.
On the other hand, reading accounts of cities as of 1850 or earlier, they sound like death traps. People are less healthy in cities. Life spans are shorter. Poverty is Dickensian. I picture pre-modern cities the way I picture Russia today: people living off government assistance or criminal enterprise or sale of personal belongings; death at an early age; etc.
I wonder: who came to cities? Was it people without land? Were cities like an awful lottery that people would play when they had no other choice? A bunch of landless people gathered together to prey on one another, with the winners thriving (moving to the country as soon as they could afford it) and the losers enduring a Hobbesian existence, where life was nasty, brutish and short?
Did that make America in the eighteenth centuray seem like paradise, with its endless supply of land? Why were there cities in America? Was Jefferson's preference for yeoman farmers a natural reflection of the relative state of urban vs. rural existence?