Harry as king fics usually weave a wild mix of ancestry reveals, political AU world-building, and a hefty dose of wish-fulfillment. The most common route is through a massive lineage twist: Harry discovers he’s not just a Potter, but a direct descendant of King Arthur Pendragon, Merlin, or some hidden magical royal line like the Peverells. Suddenly, ancient magical contracts or artifacts like the Sword of Gryffindor or the Goblet of Fire activate his ‘rightful’ claim. Some stories have him conquering the throne after winning the war, with a grateful or fearful wizarding world and muggle government bowing to his power. It’s a trope that leans hard into power fantasies and political maneuvering, where Harry often gets a harem and overpowered abilities along with the crown.
I’ve seen a few that try a more realistic merger, where the Statute of Secrecy falls and magical Britain needs a single figurehead to negotiate with the muggle prime minister. Harry, as the savior, gets shoved into the role. The execution varies wildly—some are serious political dramas, but many are just crackfics where he ends up ruling both worlds because ‘why not?’ The appeal seems to be about giving him ultimate authority and a clean slate to rebuild society, but honestly, most of these plots feel like they jump the shark halfway through. I still read them sometimes when I’m in the mood for something completely unhinged.