So don't set out and try to shoot a high contrast shot unless you find a good opportunity with the right lighting. Try shooting on an overcast day. It will soften the whites and blacks and result in a B&W image with more depth and gradient between the light and shadows.

Answer. The reason why the photographer chose to manipulate the picture was because he wanted to create a coping mechanism for the soldiers and the civilians during the civil war.

If the subject matter and intended message of the photo are more important than the eye candy of vivid or eclectic colors, then black and white is the way to go.