Literary critics refer to Henry IV Part I as a "history play," a genre that portrays English historical events (by which we mean, history according to Shakespeare) that resonate with current political issues, including matters of kingship, constitution, and rebellion. We also want to point out that it's easy to distinguish both parts of Henry IV from most other history plays because, in these two plays, Shakespeare blends the comedic antics of fictional characters (like Pistol, Falstaff, and Mistress Quickly) with the high matters of state that concern historical figures (like King Henry IV). Here's how this genre breaks down:
Portraying English historical events: The play covers the latter part of King Henry IV's reign and the coronation of his son, King Henry V, who was crowned in 1413. Of course, Shakespeare portrays history according to Shakespeare, which means the play sometimes strays from the "facts" and tweaks little bits of information that Shakespeare gathered from sources like Raphael Holinshed's Chronicles. Since Shakespeare is working with a five-act play, he tends to compress time, which is no big deal since the play doesn't pretend to be a history textbook. This play, along with Henry IV Part I, is primarily interested in how English history shapes the present, which brings us to our next point.
Historical events resonate with current political issues, including matters of kingship, constitution, and rebellion: When we say "current" political issues, we mean around the 1590s, when the Henry plays were written. The drama surrounding Hal's succession to the throne, for example, dramatizes the anxieties that Elizabethans likely felt as their unmarried monarch, Queen Elizabeth I, was aging and didn't have an heir to take over when she died.
Spicin' up "History" with a little fiction: Like we said, Shakespeare blends his portrayal of historical figures with some fun fictional characters like Falstaff, Mistress Quickly, Pistol, and the rest of the rowdy Eastcheap gang. This was a pretty nervy thing to do at the time. "Mingling kings and clowns" on stage was sort of frowned upon, especially by the famous poet Sir Phillip Sidney.