The Zelda series timeline is… complicated. Whether or not it was originally intended to be that way is a matter of opinion, but the fact remains: Zelda is complicated.
Hyrule Warriors is regarded as a non-canonical installment in the series as a whole. But to be honest, with the way it’s set up, it actually slots quite nicely into the convoluted timeline, albeit mostly unfolding in its own separate little corner, largely (but not completely) divorced from the main paths down which the series’ narratives progress.
Let’s take a look at how Hyrule Warriors fits in with Zelda lore as a whole… as well as how the series got to the state it’s in today.