Depiction of the battle in the Franco-Prussian War. 1896 photogravure of the painting Bazeilles (1870), by François Lafon (1846-1890).
The photogravure was created by Boussod, Valadon & Co. for an exhibition in an art gallery; the sepia tones are a rather interesting effect to choose.
The original artwork is out of copyright worldwide. The photogravure is over 100 years old, and photogravures are a strictly mechanical process and thus can't gain copyright anyway, so this whole artwork is out of copyright.
I cleaned it up, spending a few hours on it, and thus have a right to a copyright under British law, but noone else does.