Power
"Henry IV, part 1" offers an elaborate meditation on kingship. As a monarch who has usurped the throne and alienated his most important allies, King Henry must figure out a way to maintain power while the rebels challenge the legitimacy of his reign. The play also considers the qualities and characteristics that make one a good leader by examining the younger generation.
Family
Family relations are at the heart of "Henry IV, part 1". Shakespeare is particularly concerned with father-son relationships between Hal and King Henry, Hal and his surrogate father-figure, (Falstaff), and Northumberland and Hotspur. On the one hand, the meditation on family relations offers a way for the play to humanize the historical figures Shakespeare makes into characters of political intrigue. Yet, the play also reminds us that civil war and the struggle for the crown is a family affair. Male relationships dominate the play, but Henry IV Part 1 also takes a look at husbands and wives. As it contrasts the relationships between the Percys and the Mortimers, it explores Elizabethan notions of gender and sexuality.
Principles
While "honour" is perhaps the play's most important theme, it's also the most difficult concept to pin down. In the mouths of various characters, the definition of honor ranges from being synonymous with an individual's courage on the battlefield to a mere "word" used in an attempt to elevate the physical horrors of warfare to something more lofty and intangible.
