Ethnographic Arms & Armour - German Butcher Bayonet ID?

That's a "sawback removed" so-called "butcher blade". A 98/05 German Sawback Bayonet issued to Pioneer troops (Sappeurs, Sappers, Zapadores, Engineers) and to NCOs (as rank perk). The sawbacks were used to cut posts, wood, wire etc...

The British began a propaganda campaign to devilfy the german soldiers saying that the bayonets were cruel, and designed to make British soldiers suffer. Interesting, since they had used it themselves in the near past. As a consequence, German prisoners were supposedly shot on the spot if caught with one.

At the time, both Germans and English were tired and reluctant to further engage each other in Battle. Live and let live, I guess. The resultant animosity left by prisoner executions and revenge-executions well played a role in waking up futher animosity between both combatants.

This reminds me of the poor Spanish Militia captured during the 1898 Spanish-American War, and who used copper-clad bullets for their old M1873 Remingtons. Verdigris developed under tropical conditions, and there we got 1. Hearst so-called "poison buillets", and 2. summarily executed prisoners.

As German soldiers were dropping their "sawbacks" by the roadside, the Germans decided to remove their serrations in 1918. I'm not sure if the Geneva Convention got involved in that. AFAIK, the "sawbacks" basically only saw service in the rear lines.
The spine mark suggests ithis one was made in 1917, and belonged to the German Bavarian Army under "Konig" Ludwig III. The ricasso shows it makers were "Fichtel und Sachs".

Another characteristic of this maker is the square oil-hole on the wood grip.