The Japanese. They're the first known group to explicitly represent Emoji, unlike the older Latin derived systems which could only represent emotion through character combinations and thus were lame rather than complete.
https://one-from-nippon.ghost.io/story-of-the-emoji/
Doesn't talk about kaomoji though which I think are supercool. Like this table flip: ( ╯ ° □ ° ） ╯ ︵ ┻ ━ ┻