By this time twenty years of solitary confinement had disturbed Ivan’s mental equilibrium, though he does not seem to have been actually insane. Nevertheless, despite the mystery surrounding him, he was well aware of his imperial origin and always called himself Gosudar (Sovereign). Instructions had been given not to educate him, but he had been taught his letters and could read his Bible.

I was most curious if like, he was even aware. Reason being Anne Frank doesn’t remember much from before she knew language, only what she remembers as (very vague paraphrasing) primative instincts to want ice cream.

But it seems he was taught enough to understand his situation. Not sure if that’s better or worse.

Edit; yes, Helen Keller, not Anne Frank