If you are talking about Arthur (?) Birling, the father, then that is exactly what he was. A man who has joined the middle classes from a solidly working-class background, and has done various things in his life to cement his place there. In doing so, he is trying to forget his past, and there is more than a hint in the story that the treatment of the suicidal girl comes as a consequence of his family forgetting its roots.
I've just checked Wiki - there is a load of useful stuff there.
