US Navy At Dartmouth
Was Germany behind the 1918 Flu virus that killed 50-150 million people?
Admiral Hall, Chief of British Naval Intelligence during WW1, supplied information to an American legal claim against German sabotage within the USA.

The claim was originally meant for compensation for the Germans blowing up a chunk of Manhattan in the biggest terror attack in US history pre-9/11.
But when Major Peaslee, heading the US investigation, read copies of the British intercepts of German traffic and ciphers, he discovered that the Germans were not just blowing up US munitions depots (before a declaration of war); they were using biological warfare on a large scale.
It is quiet public knowledge that Germany was using Anthrax and other biologicals on cattle, with 1000s of animals heading for the Allied war effort infected by German agents at various ports. But in 1916 the Germans had discovered a flu variant that killed by over-stimulation of the immune system, therefore perfectly targeting the healthiest of men; Soldiers.
The links will show you that a German agent was in the US releasing their new Bio-weapon in January 1918. The same month the first recorded case of 1918 flu turned up in Maryland barracks.
Germany fought the legal case not in normal terms, but tried bribery, pressure, everything they could, to not be found guilty of the sabotage of the Manhattan munitions depot, despite the US only asking for $20m damages. They could have even settled outside of an offical 'guilty', but they didn't.
WHY? Because they knew the evidence could point to them releasing the 1918 flu.

They underestimated the effectiveness of the weapon, as it of course eventually spread to Germans via the battlefield anyway.

But they did everything they could in desperation to conceal it during legal proceedings. The US eventually won damages for the sabotage after 15 years of litigation, by which point it was 1939. So there were then other immediate things to worry about, and this has largely been forgotten. The Criminals running Germany at this point, were so confident they were about to win the next war, that they undoubtedly thought they could bury the evidence of their WW1 crimes after taking out Britain and the US, as a bonus.
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