Plenty of 'ancient' CPUs had microcode.
68K, System 360, Sperry 1100, and even the 'ACE' to name the great grand daddy of them all had microcode.
Technically the 6502 and the 6800/09 did not, they used a dedicated decoder that was closer to a statemachine than microcode, even though both were implemented in hardware.
None of the smaller CPUs had 'loadable' microcode, but plenty of the larger ones did.
Anyway I feel like the answer to the chicken and egg problem originally posed is to point out that things used to be different. Tools such as text editors and compilers are merely modern syntactic sugar.
And now that you've challenged me I can't remember where I saw this piece of information. Time for a quick web search.
Found something, I don't think this is where i saw it first but it will do:
"Later drawings (1858) depict a regularised grid layout.[18][19] Like the central processing unit (CPU) in a modern computer, the mill would rely upon its own internal procedures, roughly equivalent to microcode in modern CPUs, to be stored in the form of pegs inserted into rotating drums called "barrels", to carry out some of the more complex instructions the user's program might specify.[7]"