This is a simplified version of the original UNIX timeline
oversimplified many connections and left out all versions that have
either died out or never got themselves started or were running
parrallel to an existing newer or older version (this includes 2.xBSD
when 4BSD was already out and the odd Linux kernels like 2.1 and 2.3).
I also sometimes moved the release date one year to make the release
fit better in the tree. The original UNIX release are all there, even
though they lead practically nowhere.
On a last note I thought I should mention that the color codes I used
are rather arbitrary but make some sense. I also tried to let trademark
UNIX systems appear on the left side of the middle while non-trademark
UNIX systems (or clones) appear on the right side.
Click on the picture for a larger
version of the image.