I've noticed that when rendering the name of a person from one East Slavic language to another, it's usually changed to the native spelling of the target language. For example, the name "Vladimir Putin" appears as "Volodimir Putin" and "Uladzimir Putsin" on the Ukrainian and Belorussian Wikipedia pages respectively. Similar examples include "Nicholas II" being rendered as "Mikalaj II" and "Mikola II", etc. I'm curious about this practice, since it appears so uniformly in East Slavic languages, and it's so rarely seen elsewhere: in English, we very seldom translate "Mikhail" as "Michael", "Lavrenti" as "Lawrence", "Evgenij" as "Eugene", "Olga" as "Helga", etc. So why do people do this, and how did this start?