the 'real name' topic is pretty interesting. All the european kings have their names localized. the normandized bri'ish call him 'charlemagne' instead of 'carl the great', but the germans will call him 'karl der grosse'. the shakespeare plays are called 'heinrich' and not 'henry'. amadeus mozart was registered as 'theophilus', and used the french version 'amadè' of the same german name 'gottlieb' (all of those meaning: one who loves god).

I think the modern day obsession with 'real names' just comes from the fact that there's a godlike state putting that one name into its databases, and thus makes it all-important to get right - as you know, you won't be able to board a flight if your name isn't the same as the one in your passport!