Back in my day, Nintendo handheld gaming consoles were region free. That's right. If a quirky little game that wasn't being localized for North America caught my eye, I could feel free to give Nintendo money in exchange for the ability to play it to my heart's content. Ah, those were the days!
But they didn't last. No sir, they did not.
It started with the DSi, a revision to Nintendo's previous handheld. It introduced region locking for titles that used DSi-specific features like the camera.