I've been playing quite a bit of it and love it.

As you have already noted, liberties have been taken with the source material but I would argue that the themes are not dissimilar. POSSIBLE SPOILERS: Emile's basic story of conscription and having to leave his daughter is probably the most accurate. Obviously the huge requirement of manpower meant that French men were conscripted into the army and forced to leave their families. His anguish over being separated from his daughter also reflects the anguish felt by French citizens who's families and loved ones remained in the occupied areas of France. Emile's daughter details in one of her letters the mistreatment of St Mihiel at the hands of the Germans and this accurately reflects the treatment by the Germans of the populations of the occupied territories, the atrocities committed by the Germans in Belgium being one such example.

Anna's story reflects the role of women during the war. If I recall correctly the narrator explains she was studying to be a vet in Paris when the war began. He role as a medic could equate to the role of female nurses in field hospitals just behind the frontlines, a role that is often overlooked. A good explanation of the role of women at the Front can be found here. Anna's search for her father however is, as far as I am aware, a complete fabrication. It would be very difficult for a woman to move around the Front as is depicted and even harder to cross lines.

Freddie's story is possibly the most ludicrous. His story of personal vengeance is a complete fabrication as is the circumstances in which the desire for vengeance originates. The Germans weren't bombing Paris for the air at that stage of the war. Freddie is more interesting because he represents an American serving with the French army. A number of Americans served in the French Foreign Legion during the war as well as the Lafayette Escadrille

The game does follow an accurate timeline of the major events such as the use of chemical weapons at Ypres, the Verdun offensive among others but the depiction of the tank at that stage of the war is inaccurate.

One of the more memorable parts of the game for me was when Anna was leaving Paris in a stolen taxi to begin the search for her father using. The depiction of the swarms of taxis carrying French soldiers is a rather light hearted representation of the famous Taxis of the Marne, the Parisian taxis that carried French reinforcements to the Front.