How did London get its name?

Answer 1

London's English name is derived from its Roman name, Londinium.

No one knows much about the origins of London, so it's difficult to say. Of course, the Romans called their settlement Londinium, and it occupied the area where the modern City of London is. London is the anglicised form of Londinium. However, it was normal for the Romans to use local place names, so there might have been a 'Londinium' before the Romans arrived in Britain, but no one can say for sure.