I’ve always heard “Ted” for Theodore and “Ned” for Edward.
How about “Hal” and “Harry” for “Henry”?
I think Peg comes from Meg. I have no proof or evidence for this, but it’s a fact.
Same way my cat “Cookie” became “Moogly”.
In the Middle Ages there weren’t very many different personal names to choose from, so a wide variety of modifications were made to those that existed. These included -
Adding a suffix (e.g. John - Johnny). Other suffixes that have dropped out of use include -kin and -cock.
Removing a syllable (Robert - Rob; William - Will).
Rhyming (Rob - Bob. Also Hob, and Nob, which have fallen out of use but are preserved in surnames like Hobson).
Attaching a syllable from another word (“mine Ann” became “my Nan” by this process).
Combinations of any of the above, which result in Margaret becoming Peggy, Elizabeth becoming Betty, William becoming Bill, Richard becoming Dick, and so on.
In the UK at least, Edwards will usually be called Ted. An example being former Prime Minister Edward Heath, known to everyone as Ted Heath, or Grocer Ted. ‘Ned’ is somewhat old fashioned over here, but you encounter it once in a while. I have never met a British person called Theodore.
Huh! My dad’s named Theodore, and goes by Ted, but he’s from North Carolina. And of course there’s other examples like Teddy Roosevelt – so that must be an American thing.
The senior Senator from Massachusetts?
The Continental Congressman from South Carolina? 
Since someone else brought it up. I work with a lot of old guys. I kid around that I can pretty much use two names and hit most of the customers. Jerry and Dick.
Now my question is, why would someone continue to be called Dick, when I would think that if that was my name, I’d be pretty aware of the OTHER connotations of the name and would probably rather be called something a little less, well, um…suggestive? Please bear in mind, my maiden name was VERY suggestive, painful and graphic and I did everything I could to not have to use it. Why would anyone WANT to be called Dick?
And yes, the statement “I work with a lot of Dicks” works both ways.
Pussy Galore?
Would you believe me if I told you it was worse? Besides, Pussy Galore doesn’t involve potential pain.
There seems to be a strong generation dependence on “Dick”. All of the men named “Richard” of my professors’ generation seem to go by “Dick”, but nobody of my generation does. Based on that, I’d guess that “dick” didn’t have the same connotation it does now, when all of those guys were growing up, and it’s probably what something means when you’re growing up that has the most impact. By the time you’re an adult, and have had your name for your whole life, it’s probably more amusing, if anything, than embarrasing, when the “kids these days” start using your name to mean something else.
Besides, any male name at all can be used to refer to the same organ, in context. And who’s to say that whatever name you use instead isn’t going to be the next generation’s “dick”?
My uncle (my dad’s brother-in-law) is named Richard, nicknamed Dick. He has used it all his life since high school. However, he and my dad both knew what a dick was; my dad tells an amusing anecdote of a double date in the early 50’s where a girl on the date kept calling his friend who was with him on the date Dick, when in fact his name was Dave. She explained that he just looked like a Dick to her. My dad says Dave and he didn’t dare laugh…
My father-in-law is Richard, known as Dick. In his baby book, his mother often referred to him as her “little dickybird.”
The only Ted I know personally is a Thaddeus.
[QUOTE=Zoe]
Nope. Otherway round. Peggy is derived from Peg.
Margaret/Marguerite -> Meg -> Peg -> Peggy
My Great Aunt is known as Peggy, though her real name is Marguerite.