For the few who still don't know this, original concept of Boba Fett was a spinoff from a much earlier concept.
The "supertroopers". All white costumed super elite force stormtroopers.
This concept was dropped in favor of a single character that was transformed into what we know as Boba Fett.
I've always speculated that part of the reason this supertrooper costume was so extremely tricked out was because the prop/costume guys had nothing to work on before getting some direction for the SW sequel, so funneled all their creative juices into this character.
Also, I think they wanted something cool that could be used for touring along with Vader and all the tricked out gadgets (like the flame thrower, smoking rocket pack, and mic and speakers inside the armor) would make for quite the crowd pleaser.
So when exactly did the idea for the supertrooper come about?
Here is what we know:
5-25-77: ANH is first released in theatres.
1-?-1978: This is the date of the earliest concept drawings we have seen.
6-28-1978: Test footage of the supertrooper costume was shot.
11-?-79: The earliest shots of the PP1 Boba Fett costume on tour (which is what the Supertrooper was converted into).
So then I see this photo in the Making of Star Wars book pg. 239.
It shows a concept drawing of the supertrooper helmet posted on the wall.
The caption reads, "Ben Burtt in his basement editing suite at Park Way"
Now the question is, when exactly was this photo taken?
Was it taken after ANH, or during the ANH editing process?
Judging by the storyboards on the wall, they look like ANH storyboards.
And why would there be a Supertrooper concept drawing mixed in with them?
So was the Supertrooper conceptualized during the production of ANH?
If so that would make it much earlier than we ever thought.
***There are parts lists for the supertrooper where they actually label the character as "supertrooper" and has the production title of "The Empire Strikes Back".
Another question would be, how long during or after ANH, did Lucas know what the title of the ANH sequel would be?
PS, thanks to Art Andrews for the above dates.
Here are the photos I'm referring to: