I personally don't think
Chuck as a pet form of
Charles is from the Shakespearean term of endearment.
Here is a link to the newspaper column I wrote on this a while ago for my nephew's birthday. As you can see the first famous
Chuck was the original
Chuck Connors (1852-1913). Although he was actually born "
George", when he died his obituaries called him "
Charles", showing that
Chuck was then accepted as a pet form of that name. In Connors' case the nickname either comes from chuck steak (which is what he himself claimed) or is, (more likely, I think) a use of the Chinese name
Chuck for a man who was called "The Mayor of Chinatown."
http://www.omaha.com/living/cleveland-evans-popularity-of-charles-grows-from-charlemagne/article_c138c7ea-16f8-5a65-ba64-5584ebb3a42b.html#cleveland-evans-popularity-of-charles-grows-from-Charlemagne
Whatever its origin, I agree that
Chuck was taken up as a pet form of
Charles because there wasn't a short one syllable nickname for it like
Jack for
John and
Frank for
Francis, and Americans around 1900 thought
Charles needed something like that. :)
This message was edited 11/24/2015, 11:09 AM