If we look at the structure of the play Macbeth it will be seen that the it starts and finishes with a civil war. This is done purposefully by Shakespeare to highlight some important aspects of the play. .
Firstly the wars are used to make an impression on the audience. The first is used to hook the audience and keep them interested in the play. War and blood had a great appeal to the lower class audience of Elizabethan times, and was one of the features used to appeal to all social classes. This war scene as well as the first scene with the witches gives the audience a feel of what might come later in the play. The final war scene also makes a big impression on the audience. Shakespeare ends the play with a bang, and rounds off the play nicely, leaving the audience with a feeling of exited satisfaction. Both first and second civil war have a large impact on the audience and play a vital role in the structure of the play. .
The second major role of the civil wars is to highlight the changes in the character of Macbeth. In the first war he is praised for being a brave hero and fighting for his king. This is where we are first really introduced to Macbeth and we see him in an honorable light. However this is in great contrast to that at the end of the book where we see his change of character in quite the same situation as to that in the beginning. The audience now sees that Macbeth is mad with ambition for power and escape from guilt. This contrast may also stir a little sympathy for Macbeth within the audience, because we see the tragic situation he has put himself in. We also see many characteristics of Macbeth during these wars. We see him show courage, bravery, strength and ambition that could all be attributed as positives. .
The civil wars are also used to highlight a few of the theatrical effects that Shakespeare uses throughout the play. Firstly the first war is an example of proleptic irony.