The story is set in early twentieth-century Britain. The world is struggling with an economic downturn and there is a political struggle between various ideologies like capitalism in Britain, Communism in Russia etc.
Symbols like Eva representing the working class and the Crofts representing the aristocrats is quite prominent. The story also reveals this extant societal composition with stark differences present between its components classes like working-class and aristocratic rich class, Arthur Birling’s statements about Germans, labour classes etc represent this divide.
The abuse and mistreatment of Eva by Eric and Gerald also indicate the predatory and exploitative nature of the rich men preying on the misfortune and circumstances of vulnerable women.
The speech of Inspector declares such abuse and rampant exploitation of the most vulnerable sections of human society and the lack of regret in the characters (save Sheila) prove the level of hardened hearts and paucity of empathy present in society of the time.
No wonder that the following decades saw two of the bloodiest war in the history of human civilization. It calls for the end of human follies of greed and inequality of opportunities and choices.
The end of World War 1 produced this opportunity to take stock and learn from such vices. However, the world ended up in flames again in 1939. The post World War 2 era witnessed the eventual realization of human suffering and gave impetus to movements like anti-colonialism, UN and the new world order etc.
The ending though highlights the fact that evil and oppression may have a reprieve for some time but eventually balance and justice is restored. This is true in the case of the Birings and the Crofts who ended up being investigated for the suicide of young Eva Smith.