Originally Posted by Duncan Gardner
Charlton isn't geographically isolated- it's 7-8 miles from central London, served by plenty of trains (usually), and with an underground station and even an airport just up the road :)
The Irish community (in the widest sense) is large in the three local boroughs I mentioned. Many would be descended from people working in the old docks etc. There is an acknowledged, disproportionately high incidence of social problems (alcoholism, illness etc.) amongst those identifying themselves as Irish- but this has little to do with the size of the community.
As for the other cities mentioned- Birmingham, Leeds, Manchester/ Preston, there are certainly plenty of Irish and Jamaicans but fewer Nigerians. They are very much concentrated in London.