The play starts with the Chorus apologizing for the theater’s limited portrayal of history. Act 1 opens on the Archbishop of Canterbury and the Bishop of Ely hoping to distract Henry V from passing a bill that would seize Church properties by giving Henry the Church’s approval and funds to raise an army to claim France for England. Canterbury convinces Henry that war is justified because Salic law (a law that inheritance can only pass through male heirs) does not apply in France and Henry thus has an inherited right to French territory. The French Ambassadors deliver the Dauphin’s warning and box of tennis balls. Henry conveys his contempt back and declares war. Meanwhile, Bardolph, Nym, and Pistol bicker while Hostess Quickly and Boy attend Falstaff’s deathbed.
Though France bribes the English lords Scroop, Cambridge, and Grey into plotting Henry’s murder, Henry discovers the plot in time. He toys with the traitors, letting them advocate royal mercilessness in a commoner’s case before exposing their plot and condemning them to death according to their own recommended policy. Henry sets sail for France.
King Charles, the Dauphin, and the French court receive Henry V’s ultimatum: surrender or face attack. The Dauphin scoffs. The Chorus recounts that Charles offers Henry his daughter Katherine and small dukedoms. Unsatisfied, Henry attacks Harfleur, motivating his troops by speaking to their strength and nobility. Nym, Bardolph and Pistol try to evade battle while Fluellen lectures everyone on Roman war discipline. Harfleur surrenders after Henry threatens blood-curdling violence, at which point Henry orders his soldiers to treat the French citizens mercifully. At the French palace, Katherine practices English and the French prepare to rally their army.
Back at the English camp, Henry approves Bardolph’s execution for stealing (never seeming to even think about or notice that Bardolph was one of Falstaff’s friends back when Falstaff was Henry’s mentor), promoting moral rectitude among his troops. Montjoy, a French ambassador, arrives to ask Henry for a ransom to pay back the damage he has caused to France or face total defeat, but Henry refuses to back down and says he’ll fight the next day despite his troops’ exhaustion. The two armies wait for battle the next morning: the French, smugly confident; the English, tired, ill, and fearful. Disguised, Henry wanders the English camp pretending to be a common soldier and argues with Michael Williams about the justness of the war and the king’s right to launch it. He and Williams exchange gloves and vow to fight when they meet. Alone, Henry enumerates the stresses of being king, envying a commoner’s peace of mind.
Next morning, the French charge assuredly into battle while the outnumbered English long for reinforcements until Henry delivers a speech on English honor and brotherhood. He declares that this day, St. Crispin’s Day, will forever be celebrated in commemoration of his soldiers’ bravery. His troops charge off in high spirits and overwhelm the French. A group of French defectors vandalize the English camp, killing Boy and others. Montjoy arrives to ask if the French can sort the corpses of their noblemen from their commoners and admits that the English have won. Henry names the fight the Battle of Agincourt. He gives Williams’ glove to Fluellen under false pretenses, then, after Fluellen and Williams begin to fight, reveals himself as the man Williams argued with. Henry not only pardons Williams but rewards him. A herald delivers the casualty report: France has lost ten thousand; England, twenty-nine. Henry gives God credit for the victory and calls for a religious procession and Christian burials before returning to England.
The Chorus recounts Henry’s modesty in England and his subsequent return to France to negotiate a peace treaty as requested by the Holy Roman Emperor. The final act opens in France where Fluellen fights Pistol for daring to make fun of the leek he wore in his cap to celebrate St. Davy’s Day. Gower backs Fluellen up, warning Pistol not to make fun of people’s different cultures. Meanwhile, Henry, King Charles, Queen Isabel, Katherine, and French and English nobles gather at the French palace. Henry agrees to peace on the condition that Charles accepts his demands, which Charles goes off to review. Henry woos Katherine (marriage to her is his foremost demand) by presenting himself as a simple soldier. Charles returns to announce that he grants Henry all he asks for and blesses Henry and Katherine’s betrothal, hoping that their marriage will prevent all future strife between England and France. The Chorus closes the play by describing how Henry’s son loses France in the next generation.