This is interesting. Several programmes have aired in the UK on the lines of "World War 1 (or 2) in Colour" and I agree that the archive material has an immediacy and a "reality" that monochrome can't give. But the implication is (and I think it's been specifically stated in many instances) that the film is genuine colour footage from the period.
New words, one handy idiom, and a 2-minute quiz — delivered to your inbox to keep your streak alive.