The companion of ASCII back then was IBM's EBCDIC. You can research which one was first.

As you surely know the AS in ASCII stands for "American Standard". That kind of implies that there were earlier non-standard encodings in America and also other encoding used outside of America.

Also realise that ASCII originally was a 7-bit code, and you see that you asked a very, very vague question. So vague that it is unanswerable.