Everyone thought that Harry Potter was such a great hero, so perfect, so much that apparently, they believed he could do everything! The Ministry would call him in for the most mundane of issues—"Oh, Harry, we've misplaced a file in the Aurors' Department, help us find it?" "Harry, we've gotten suspicious news of the Malfoys." "Harry, this, Harry that"—it was bloody infuriating!
He was the Head Auror, the Man-Who-Conquered, not the Ministry's bloody lapdog! He rather thought that'd be obvious, considering he'd made it clear he hated the Ministry since his third year at Hogwarts, but apparently accepting the position of Head Auror—which people forgot had been practically forced onto him—completely negated all of that.
It had gotten to the point where even Ginny had begun to accuse him of neglecting their family—at first just as a joke, then with a smile that didn't quite reach her lips. It was easier with the kids, who were away at Hogwarts, but even with them it became strained once Hogwarts had let out for the summer.
It wasn't too bad with James, who was a third year and therefore undergoing a rebellious teen phase, and Albus, who was a bright-eyed first year still amazed by his first year at Hogwarts (Harry himself felt very sentimental—Albus being his carbon copy with Ginny's eyes made him even more melancholy about the simpler times), but Lily, who hadn't yet received her acceptance letter and had therefore been home the entire time, had begun to spend the majority of her time ignoring Harry.
That had been the last straw. Nothing that made his adorable ten-year-old daughter upset ("Or," Ginny commented, "anything that makes daddy's little girl ignore him. Wrapped around her finger, you are,") was something he was going to condone.
So he took vacation leave, and left Ron in charge. He knew that when he came back, he would probably find half of Wizarding Britain in shambles—because, even though Ron was his best friend, everyone knew he was terrible at deskwork and management—and he knew that it was probably a terrible idea, but he found that he was just too utterly irritated to care.
He also decided that he did not want to deal with the Ministry at all. This would happen as long as he was in Britain—so at first he'd contemplated taking Ginny and the kids to France to visit the Delacours, or visiting the Krums, but then he realized something. All of these people were influential across Europe—as long as he was around family and friends, he have to deal with some sort of a ridiculous Ministry praising or ridiculing the Man-Who-Conquered.
This lead to the genius idea of taking an overseas vacation. Unfortunately, Ginny was of a different opinion on the 'brilliance' of his idea.
"America? Are you bloody out of your mind!? You don't talk to us for days and all of a sudden it's, 'Let's go to bloody America!'"
"But don't you see, Ginny?" Harry threw her a grin that bordered somewhere between mad and ecstatic. "It's perfect! No one will bother us there! Just us, and the kids!"
His tone became wistful. "Besides, I've always wondered what magic's like across the pond, ever since I'd seen the Salem tent in that World Cup back in our fourth year. Never did have to chance to see."
Ginny looked at him suspiciously for a second, probably wondering if she was trying to bat her sympathy, then sighed. "This is insanity," she said.
Harry's grin widened. "I'm Harry Potter, remember? That is why you married me."
And so in the summer of 2015, the Potters took a trip to America. Specifically, a place where most would think not much happened, because they wanted to avoid attention, and which happened to be the home of a girl who went on a journey through the magical Land of Oz in a search for a wizard—Lebanon, Kansas.