"Fact" is he has a father who was a UK (Scottish) citizen and a mother who was a Swiss citizen. That's it.
Though by inference in the novel Live And Let Die, he's not black, but it's never stated as an explicit fact
Vesper Lynd in the CR novel: "Bond reminds me rather of Hoagy Carmichael, but there is something cold and ruthless."
And I hope nobody's suggesting "something cold and ruthless" means "black".