The story is set in Messina. Located on the island of Sicily, Messina, as Shakespeare describes it, is a quiet European town that appears to be isolated from the conflict and strife that so often occurs in larger cities. Messina is an idealistic village that is undisturbed by war and political intrigue. For this reason, the town serves as a type of resort where people from the large cities can stop and rest and get away from the hectic problems of daily life.
Shakespeare does not indicate a date or year when the events of his play occur. The story is like a fairy tale with a once-upon-a-time atmosphere. The story itself has a fairy-tale quality that is magical and timeless and universal. Yet, as the events of the story suggest, Shakespeare probably had in mind the 15th century when Sicily was ruled by relatives of the kings of Aragon and later became part of the kingdom of Aragon itself. Aragon was a separate kingdom in the northeast part of Spain until the early 18th century. In Shakespeare's tale, the people of Messina are concerned about the events affecting Aragon, but they do not seem to be directly connected to those events.
The governor of Messina is an easy-going and friendly old gentleman named Leonato. In his household live two young women: his daughter Hero and his niece Beatrice.
As the play opens, Leonato speaks to a messenger who has just delivered a letter from Don Pedro, the Prince of Aragon. The word Don is not a name: rather it is a title of respect for a Spanish nobleman (not unlike the way Sir is used in England). From the message Leonato learns that Don Pedro and his military troops have just won a tremendous victory in battle and are coming to Messina for a period of rest and relaxation. Shakespeare does not indicate where the battle occurred and who the enemy was. These events are unimportant and irrelevant to the love story that forms the core of this story. What is important is that Don Pedro and his men are leaving the worries and cares of the civilized world behind and are ready for amusement and entertainment.
From the message Leonato also learns that Don Pedro has in his service a young officer named Claudio who has performed in the battle heroically despite his young years. Once again Shakespeare purposely avoids being specific. The playwright does not specify Claudio's acts of heroism and feats of bravery. Rather, for the purpose of the story, the only detail that the audience needs to know is that Claudio is a hero. Shakespeare uses a fine metaphor to establish this idea: Claudio has "the figure of a lamb" but has performed "the feats of a lion" (line 12). Claudio looks sweet and young and innocent, but he is a brave and heroic and worthy gentleman.
Shakespeare, in a way, tricks his audience. In this passage he appears to be establishing Claudio as the central character, the protagonist, of the play. Such an introduction would be conventional in drama. But this is actually false foreshadowing; for, as indicated above, the young lover Claudio becomes a secondary or minor figure alongside of Benedick, who is another officer serving in Don Pedro's army. Thus, Shakespeare performs a bit of stage magic, transforming a minor character into the protagonist of the play.
Shakespeare's playfulness and creativity with language may occur even in the dialogue of his minor characters. In this scene the messenger from the prince describes the success of Claudio's actions in battle with the following line:
He hath indeed better bettered expectation than you must expect of me to tell you how. (13-14)
Today, with the sometimes overly inflexible rules of language, grammarians would consider a phrase like "better bettered expectation" as improper and incorrect. However, in Shakespeare's age, grammar books did not exist and writers were free to be inventive and creative with their words; and the results were often rich and wonderful. Here, the messenger (or Shakespeare) means that Claudio has performed better in battle than even the best or highest of expectations that anyone could have thought. Yet Shakespeare expresses this concept with three concise words; and even though this phrase would be new to Renaissance ears, everyone in his audience would have easily understood it.