Living in the Victorian Age in which industrialization was changing society, Charles Dickens felt that society in England was a prison. In the rural areas there were landlords, the owners of large farms, and farmers and common laborers who owned no land, but merely existed on a subsistence level by working on the large farms. With the invention of the steam-powered engine, thrashing machines took the place of many of these laborers. Consequently, the poor rural people flooded the city of London where they, along with the other poor of London, sought work in the factories. In their efforts to survive, these people sent their children to work as well. Since their jobs were unskilled laborer jobs and there were no labor laws of any kind in England at that time, the poor were condemned to poverty forever.
Having had a father placed in debtors' prison and having had to work in a blacking warehouse as a boy himself, Charles Dickens was most sympathetic to the poor, a class who was ignored by what he perceived as a frivolous upperclass who controlled all the wealth. In fact there was only one major bank, the Bank of England, which dealt mainly with government contracts because businessmen conducted their financial dealings privately among themselves. Since there was little hope for social mobility, many of the poor who sought their fortune during the Industrial Revolution found themselves in workhouses and prison, or they turned to crime. Since money was made in London, criminal activity increased there. (Magwitch is one of the poor who survives by petty crime.)
As higher-level workers in factories and merchants prospered from the industrialization, a new middle class emerged (Uncle Pumblechook is an example) and the need for banking arose. Banks, thus, became more numerous as the need for borrowing for new businesses arose. (Pip's procuring a job for Herbert is made possible by this growing banking business.)
It was not until 1860 that the railroad connected the city to the rural areas of England. (This is why Pip must take the stagecoach to the Boar's Inn whenever he returns home.)