Michael Hohmuth writes:
No, Fiasco is not the first kernel written in C++. I can think offhand of at least two other kernel projects using C++: Chorus and Off++.
Choices, (see http://choices.cs.uiuc.edu ) was a nice kernel done in C++ to demonstrate that was feasible (that work was a phd thesis). They implemented a uKnernel version uChoices, which was also extensible by downloading java.
-Nemo.