The play is first and foremost a historical drama. It depicts a major historical event, and its characters are all historical figures who were key players in that event. Historical dramas often do not attempt to depict history exactly as it happened. Instead, especially in the 20th century and beyond, they often attempt to delve into the psychology of their characters and imagine the emotional realities of living through the major event at hand. Shaw's play is no different. In fact, Shaw explicitly states in his preface that he wants to show the main players in the Joan of Arc story as flawed humans, one and all. Joan had recently been made a saint, and it bothered Shaw how many artistic interpretations popped up lionizing her and demonizing her persecutors. He wanted to offer an interpretation that didn't flatten all the characters into heroes or villains.
While Shaw's play aims to capture emotional realities from this moment in history, it also revises some of the facts. Most notably, Shaw makes his play about modern nationalism, when this political ideology was anachronistic for Joan of Arc's time. The anachronism is key to understanding the play as a social and political satire (a genre to which most of Shaw's work belongs). Shaw uses Joan of Arc's story to comment on nationalism in the 20th century. For instance, the play indirectly suggests that a united Ireland would be more successful than a divided one. It does this by satirizing all of the characters who resist the French "nationalism" Joan advocates. These characters are not evil monsters, Shaw suggests. They are simply selfish and shortsighted, just as he believes modern opponents of a united Ireland are selfish and shortsighted.
