On July 24, 1915, the World War was raging in Europe and the belligerents were vying for the sympathy of the neutral United States. In Lower Manhattan, on a Sixth Avenue elevated train, Secret Service agents were tailing George Sylvester Viereck, a German propagandist and a mysterious companion of his—who was, unbeknown to the agents, Heinrich F. Albert, an attaché in the German Embassy. When Viereck got off at 23rd Street, one agent followed him; Albert continued on to 50th Street, where he suddenly looked up from his newspaper, noticed he had reached his stop, and hurried off the car, leaving behind a brown briefcase that the second agent promptly seized. A chase ensued, but the purloined bag ultimately made it to Treasury Secretary William McAdoo, who shared it with President Woodrow Wilson. The documents that Wilson and McAdoo beheld detailed a sweeping secret campaign, linked to high-ranking German officials, of espionage, sabotage, and propaganda. There were plans to take over American newspapers, bankroll films, send hired lecturers on the Chautauqua circuit, and create pseudo-indigenous movements to agitate on behalf of pro-German policies. More disturbing were schemes to provoke strikes in armaments factories; to corner the supply of liquid chlorine, an ingredient in poison gas, in order to keep it from Allied hands; even to acquire the Wright Brothers’ Aeroplane Company and use its patents on Germany’s behalf.
more from David Greenberg at Slate here.