The play is set in 1912. At the time England had a very rigid social class structure. Broadly speaking this meant a group of upper class people who were very rich and tended to own lots of land and very large houses. The middle classes were generally those with professions such as the law or those who had made money through business. Working class people were much poorer and tended to work in places like factories or coal mines. Many working class people were unemployed and poverty stricken.
In the play Gerald Croft and Mrs Birling represent the upper classes. Mr Birling is a self-made businessman who has risen to the middle classes. Eva Smith represents the working classes.
In 1912 England had an empire and controlled large parts of the world. If you saw the Commonwealth Games last year then all the countries taking part were in the Empire at the time the play is set.
England was a generally confident country. If you were wealthy then it was probably a good place to live. If you were poor then the opposite is also true. The way of life that was in place then was about to change. Europe was heading towards the First World War, which began in 1914. The war changed English life quite dramatically, for example women began to go out to work in large numbers.
There had been major steps in industry and inventions. The motor car was appearing more frequently on the roads. In some ways the building of the Titanic could be seen as representing the confidence, or arrogance, of the Edwardian age. As you probably know the Titanic sank on its maiden voyage in April 1912. For many people the sinking of the Titanic is seen as the beginning of the end...