

What about OpenSUSE, Ubuntu etc? Both European based firms.
Canonical (based in London) is not really “from the EU” anymore. ;-) No, I know what you mean…
However: Yes, those are European Linux distributors. They distribute an U.S. operating system kernel together with an U.S. userland (GNU), an U.S. init system (systemd), several U.S. desktops (most commonly, Gnome, although KDE is German, at least)…
If you get your Windows installation from an European distributor, is it a European product?
considering their (…) contributor network.
Microsoft has employees in Europe. Does that count? If it doesn’t, why does it count for Linux?
Honestly, the EU seems to be not the best place to write operating systems.
The most actively developed version of Plan 9, 9front, is from Germany, but that’s not what most people want to use, I guess. Best I can do is non-American (OpenBSD). I’m open for ideas myself though!