On Tue, 21 Jan 2020 at 12:53, Jon Forrest <nobozo@gmail.com> wrote:
There's been a lot of discussion about early Unix on Intel, National
Semi, Motorola, and Sparc processors. I don't recall if Unix ran on
the Z8000, and if not, why not.

A tiny bit of research would have answered this question for you: https://en.wikipedia.org/wiki/Zilog_Z8000#Z8000_CPU_based_systems