Multics Emacs: The History, Design and Implementation (1979)
multicians.org
multicians.org
And RMS makes no secret of that: https://www.gnu.org/gnu/rms-lisp.html so I probably learned this before at some point.
No, the first Emacs in Lisp was the one from Dan Weinreb for the Lisp Machine, which was also the second Emacs implementation. It was called EINE, EINE Is Not Emacs. Then ZWEI, ZWEI Was EINE Initially.
Check out the gorgeous Creative Computing ad:
https://en.wikipedia.org/wiki/MINCE
And contrast with the ugly UniPress Emacs ad:
If you edit please try Emacs.
PROGRAMMER GENERAL'S WARNING: Inferior
Editors Cause Decreased Productivity Or
Vaporware And May Complicate Development.
UniPress Emacs: Less than 90MB "tar"(1).
Also ZMACS is ZetaLisp eMACS:https://en.wikipedia.org/wiki/Zmacs
And CLIMAX is Common Lisp Interface Manager emACS:
https://en.wikipedia.org/wiki/Climacs
Of course JOVE is Jonathan's Own Version of Emacs:
https://en.wikipedia.org/wiki/JOVE
Sadly ZILE is Lossy Emacs:
https://en.wikipedia.org/wiki/GNU_Zile
Worse yet, VILE is VI Like Emacs:
He's spread his knowledge of music theory with many, including me, on the (opensource) musescore website.