The origin of the word dude came about around the time the civil war was ending and people moved west to start new lives. It is a common historical occurrence that after a war, where large groups of people are together, the language grows, shapes, changes, and is taken back home for common use.
Dude was thought of as a western term for a long time. Rather than the rugged independent American spirit I often associate with dude, I have come to learn that it meant “dandy.” More to the point it was an eastern dandy moving west to try his luck, but had little respect or knowledge for the open range.
The first time dude was used in literature was from Mark Twain in “A Connecticut Yankee in King Arthur's Court.” Hank Morgan, our protagonist in this social satire, refers to the knight as “Ye Iron Dude.”
The lure of dude was in later ranching days of California when ranch hands tough and leathery were called dude. But that got twisted sometime in the late 1960’s early 1970’s. People who used words like “reefer” instead of refrigerator or the intellectual giants that called the television the “boob-tube” now added dude to their extensive repository of words.
Do I need to go on with turtles in “Finding Nemo”, the main character simply listed as “The Dude” from “The Big Lebowski”, a full scene of dialogue in “Baseketball”, or “Dude Where’s My Car?”
Dude has come full circle, from dandy, to tough man, back to fool.