500 Wedding Ideas - What means "britishness" in a film Four weddings and a funeral?would you say its contrast between Eng/americ?

What means "britishness" in a film Four weddings and a funeral?would you say its contrast between Eng/americ?

the topic is to discuss british national identity-demostrated on the film Four weddings and a funeral.

I have not seen the movie. But basically Britishness in a movie would mean the accent and the behavior of the people. Even the daily chores are different.