Book Review: Treacherous Passage: Germany’s Secret Plot against the United States in Mexico during World War I


by Bill Mills

Lincoln: Potomac Books / University of Nebraska Press, 2017. Pp. xii, 226. Illus., notes, biblio., index. $29.95. ISBN: 1612348548

Fresh Light on Imperial Germany’s Covert War Against the U.S.

Well before the American entry into the Great War, German agents initiated a still poorly understood covert “war” against the United States, and while working on The League, his book about the Justice Department’s volunteer detectives in World War I, author Mills came upon a curious incident involving some German agents and the vessel Alexander Agassiz incident, Mills uncovered evidence of one aspect of the elaborate German conspiracy against the United States

Working through contacts in the German ex-patriate community in Mexico, German consul Fritz Unger developed several schemes intended to divert American attention from Europe, to keep the United States out of the Great War. These included espionage, smuggling munitions from the U.S. through Mexico to Germany, and sabotage. But Unger had greater ambitions.

One scheme involved the salving of a wrecked Mexican gunboat for commissioning into the German Navy as a commerce raider that would operate in the Pacific. In addition, using German reservists who had been unable to get home from Mexico on the outbreak of the war in Europe, Unger undertook to recruit a German-officered Mexican army to carry out an invasion of the United States, and apparently received some help – or perhaps merely encouragement – from Mexico’s revolutionary leaders Venustiano Carranza and Plutarco Calles (remember, this was a period of great tension between the United States and Mexico, leading to the Pershing Expedition).

The book is well populated with agents, double agents and possibly even triple agents, most notably the interesting and shadowy Paul Bernard Altendorf, but also Unger himself, the owners of the Pacifico brewery, and more. A lively read, Treacherous Passage, although not yet the full story, is not only a good cloak and dagger tale, but also throws further light on the still-not fully documented German efforts to carry on covert operations against the United States during the Great War.

Note: Treacherous Passage is also available in several e-editions.


Reviewer: A. A. Nofi, Review Editor   

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