Why do they call guys named John...Jack?

Answer 1

The English Jack is derived from Jankin -> Jackin (form of Jehan -> Jan ->
John). Names are words, and how they were spelled depended in large part
on how they sounded in times past. Vowels change a lot.

Answer 2

Ok basically in the past people were more creative in using nicknames for first names than we are now. There are several older nicknames that don't appear to relate well to thier root name, but if you look more closely you can see that they were derived from some of the vowel sounds in the formal name for example Name-> Nickname-> Derivative Nickname Margaret-> Meg-> Peg/Peggy Richard-> Rick-> Dick Robert->Rob->Bob Edward->Ed->Ted William->Will->Bill Elizabeth->Beth->Betty->Betsy or Elizabeth->Liz-> Liza->Lisa Basically in the past people would play with nicknames more than we do now and the ones that sounded the best stuck with the user and were used again and again such as Peggy for Margaret, Dick for Richard, or Bob for Robert, Betsy or Lisa for Elizabeth. People just picked the nicknames they liked and sounded good, and some became traditional. Also many people at that time shared the same names so creative nicknaming was necessary for distinguishing people. Some of the names we now consider distinctive names were once considered a nickname for another name. For example Molly and Polly were both originally nicknames for Mary and Sally was a nickname for Sarah.

Answer 3

I've known several "John"'s in my life (I was actually married to one) and I've never heard anyone call him or any of the others "Jack". This is news to me.

Answer 4

I think this derives from the french name Jacques ... anglicised to Jack

Answer 5

It's a nick name - like Dick is Richard...

Answer 6

THIS IS NOT A GENEALOGICAL QUESTION!!!