* The dangers of pride and ambition: Henry IV's pride and ambition lead him to betray his former allies, the Percys, and to engage in a civil war that ultimately results in his own death.
* The importance of loyalty and friendship: Henry IV learns the hard way that loyalty and friendship are essential for a successful reign. He loses the support of his allies, including the Percys, and is eventually betrayed by his own son, Prince Hal.
* The power of love and forgiveness: Despite all of the conflict and betrayal, the play ends with a message of love and forgiveness. Prince Hal reconciles with his father, and the two of them are able to move forward together.