It has always puzzled me how one gets 'Jack' from John. Both contain 4 letters. I read it's a variant from the medieval Jackin/Jankin. Weird because in French, Jacques is actually James or Jacob, Jean is their equivalent of John. Sean, Ian, Ifan/Evan, Ewan are all Johns (not to be confused with toilets.)
it's all really interesting when you get into it. Makes one wonder if before there was actual language, if sounds were made, like grunts, whistles, etc. as names? Those same grunts, moans, groans, clucks, tuts, hums, whistles, etc. were/are the origin of forming words, actually, and we've really elaborated and expanded on them a LOT since then.
Anyway, back to name calling. Take Robert, as another instance. It has many, many variations, as do most names, I'm sure, in the evolution of words in general.
It is one that has multiple 'nicknames', some which not only serve as nouns, but verbs, as well:
'Would Rob rob someone whilst they bob for apples?' Could it be both minor felony/misdemeanor and a possible homicide? A Bobby should be called.
It's like the current use of the nickname for Richard. 'King Dick the third' was from a long line of Dicks. Um, yeah.
K, so this is going nowhere now.
I just find it (and most EVERYTHING) so incredibly interesting.
My given name, for example, is a demon in one culture, yet a deification of mother earth (as well as a psychopomp that escorts the spirits of the dead), in another culture. Kinda makes me like a cenobite, huh?
Welp, that's all I have to say about this. Actually, not really, I just have to go eat supper now! :)