EWW was originally written by Lars Ingebrigtsen, known for his work on
Gnus. He started writing an Emacs HTML rendering library,
shr.el, to read blogs in Gnus. He eventually added a web
browser front end and HTML form support. Which resulted in EWW, the
Emacs Web Wowser. EWW was announced on 16 June 2013:
https://lars.ingebrigtsen.no/2013/06/16/eww/.
EWW was then moved from the Gnus repository to GNU Emacs and several developers started contributing to it as well.