An Inspector calls was written in 1945 just after the second World War, a time of Great change and opportunity. The play is a three-act drama, which takes place on a single night in 1912, the era of the Titanic and World War I. This was before the days of the Welfare State and Britain was a country deeply divided by class. This means that there is a lot of opportunity for the dramatic irony because the audience know more than the characters; Irony is different than dramatic irony, it can be similar to sarcasm; Priestley uses also dramatic irony to display Mr. Birling's arrogance and foolishness; in fact in the first scene Mr. Birling explains, to the dinner party, his beliefs on the world, that is there’ll never be war and that workers want go on strike and he is certain that the "unsinkable" ship Titanic will never sink so we can say that understanding the historical contest, we can understand an inspector calls. For an audience watching this in 1946, all this prediction showed catastrophically wrong.
An inspector calls is not just about the Birling's family and an unusual inspector, in reality it is an allegory. An allegory is a story in which people, things or events represent big ideas and themes about life; this rhetoric figure is explained in inspector’s sentence: “One Eva Smith is gone, but there are millions, and millions and millions of Eva Smith and John Smith still left with us” (56).
The key themes of this play are socialism and capitalism. The socialism is a political theory or system in which the means of production and distribution are controlled by the people and operated according to equity and fairness, rather than market principles. While the capitalism is an economic system based on the private owner ship of the means of production and distribution of goods. characterized by a free competitive market motivated by profit. The Birlings represent capitalism and the inspector represents socialism. J B Priestley was a socialist (left wing). His socialism can be said to be based on compassion and caring for others. He came from a working class background and felt compassion and empathy with the factory workers who were exploited by the industrialist such as Arthur Birling. So, in the play, Eva Smith represents all poor and exploited working class, while the Birlings represent the wealthy upper classes who exploit them. Prestley links the attitude and action of the Birlings with the catastrophes of the first world war and the second world war. In fact the inspector, in his crucial finalist speech, refers to “fire and blood and aguish” that did happened in the form of two world wars, revolution and social conflict.
Priestley's message is still relevant today because the gap between the rich and the poor is growing due to greedy capitalists who want all the money to themselves.