Even before the United States threw its hat into World War Two, the German intelligence agency Abwehr was already slipping operatives into American cities and coaxing German‑American citizens onto the Nazi side. These daring undertakings produced a mix of modest successes and spectacular blunders. Below, we dive into ten German spies and the plots they tried to pull off on U.S. soil during the 1930s and 1940s.
Why Nazi Spies Targeted America
The allure of the United States lay in its industrial might, its expansive coastlines, and the relative openness of its society. For the Nazi intelligence machine, planting agents on American soil promised access to critical military technology, valuable intelligence on ship movements, and the chance to sow chaos that could divert the nation’s attention from the European theater.
10 The Long Island Landing
In June 1942, the German submarine U‑202 slipped a quartet of would‑be saboteurs onto the sands off Long Island, New York. Led by the charismatic yet nervous George John Dasch, the team was part of “Operation Pastorius,” Hitler’s ill‑fated two‑year sabotage plan that called for blowing up bridges, railways, and factories along the East Coast.
The U‑boat ran aground on a sandbar, forcing the men into a shaky inflatable raft. After a frantic scramble to bury crates of explosives, blasting caps, and timers, they were nearly caught by Coast Guard patrolman John Cullen, who stumbled onto the scene. Dasch tried to intimidate Cullen and even offered a bribe, but Cullen reported the incident.
FBI agents soon uncovered the hidden crates and traced the saboteurs to New York City. While three of the men hid in a hotel, Dasch fled to Washington, D.C., surrendered, and betrayed his comrades. He avoided execution, receiving a 30‑year prison sentence instead, gaining clemency in 1948, and eventually being deported to West Germany.
9 The Maine Mission
In November 1944, two German agents—Erich Gimpel, an experienced Abwehr courier, and William Colepaugh, a German‑American Nazi sympathizer—were dropped off by U‑1230 near Bar Harbor, Maine. Their objective was to gather intelligence on U.S. military assets and, if possible, delay the development of the atomic bomb.
Clad in ill‑suited winter wear, they trekked inland with crates full of fake IDs, guns, cameras, cash, and diamonds, catching a train to Boston and then New York City. Instead of covert espionage, Colepaugh squandered $1,500 of their funds on booze, parties, and women, eventually abandoning Gimpel and absconding with $40,000 and a dubious companion.
After a drunken binge, Colepaugh turned himself in to the FBI on December 29, spilling the beans on their mission and revealing Gimpel’s whereabouts. Both men were tried in a secret military tribunal, sentenced to death, but the war’s end commuted their sentences to life. Gimpel was released in 1955, while Colepaugh earned parole in 1960 and faded into a quiet Pennsylvania life.
8 The Trenton Sleeper
Maximilian Gerhard Waldemar Othmer arrived in the United States in 1919, became a naturalized citizen by 1935, and settled into a modest life as a vacuum‑cleaner salesman. Unbeknownst to his neighbors, Othmer was a sleeper agent for the Abwehr, quietly embedding himself in the pro‑Nazi German‑American Bund.
His espionage career took him to the Brooklyn Navy Yard, where he spied on ship movements, and later to a military base at Camp Pendleton in Norfolk, Virginia. By 1942, the Army transferred him to Knoxville, Tennessee, where he continued feeding German handlers with coded reports on Allied convoys.
An FBI probe into his overt Nazi sympathies uncovered a suspicious request for Pyramidon—a painkiller used by Abwehr agents to create invisible ink. When questioned by the Knoxville FBI, Othmer confessed to spying, handed over a microfilm of his cipher, and was sentenced to 20 years in prison.
7 Guenther Rumrich’s Passport Ploy
Born in Chicago to an Austro‑Hungarian father, Guenther Gustav Rumrich returned to America in 1929 and served in the U.S. Army’s Medical Corps in Panama before deserting in 1936. By 1938, British MI‑5 had intercepted letters between a Scottish mail‑dropper, Jessie Jordan, and a mysterious “Mr. Crown,” later revealed to be Rumrich’s code name.
When MI‑5 passed the intel to the FBI, agents set a trap. Rumrich, however, turned the tables by calling the New York Passport Office and impersonating the U.S. Undersecretary of State, demanding 35 blank passports be mailed to his address. The suspicious clerk alerted authorities, leading to Rumrich’s arrest—the first major pre‑war espionage case in America.
He cooperated, testifying against fellow agents and receiving a lenient two‑year sentence. Though his information helped expose a broader spy ring, many higher‑ranking Nazis slipped through the net.
6 The Dress Shop Spy
Lilly Stein, born in Vienna in 1914, was a former ice‑skater and tennis player who turned to espionage after an affair with U.S. State Department official Ogden H. Hammond, Jr. Recruited by the Abwehr, she set up a dress shop in New York City in 1939, using it as a front to forward letters and microfilm between Germany and fellow agents.
Her socialite lifestyle meant she rarely carried incriminating items, but she did transport microfilm hidden in clothing. Financial woes and a strained relationship with her handlers led to her removal from active service.
In June 1941, she was arrested as part of the infamous Duquesne spy ring. Claiming she was forced into espionage to avoid persecution, Stein received a ten‑year prison sentence.
5 The Norden Bombsight Blueprints
Hermann W. Lang, a German‑born draftsman who immigrated to New York in 1927, worked for the Carl L. Norden Corp., the maker of the top‑secret Norden bombsight. Recruited by the Abwehr during a 1938 visit home, Lang smuggled a set of the bombsight’s blueprints out of the factory, later delivering them to Germany hidden inside an umbrella on a cruise liner.
He continued feeding his handlers with additional details until his arrest as part of the Duquesne spy ring. Lang pleaded guilty and earned a 20‑year sentence. Government officials later claimed the full plans remained secure, though the Luftwaffe’s post‑1938 bombsight bore a striking resemblance to the stolen design.
4 The Ponte Vedra Foursome
Operation Pastorius’s second group, dubbed the “Ponte Vedra foursome,” landed in Florida in June 1942. Led by John Edward Kerling, a German who had spent years in America, the quartet intended to sabotage railways, plant suitcase bombs in Jewish‑owned shops, and cripple New York City’s water system.
After burying their equipment on a beach, they traveled by bus to Jacksonville, then onward to Cincinnati, awaiting a rendezvous with Dasch’s Long Island team. Unaware that Dasch had already betrayed his comrades, the Florida team was arrested when Kerling’s scheduled meeting was reported to the FBI.
All four men faced a military tribunal and were executed by electric chair in August 1942, alongside two of Dasch’s group.
3 Dr. Ignatz Griebl, Spymaster
After serving in the German army during World War I, Dr. Ignatz Griebl immigrated to the United States in 1925, settling in Manhattan’s Yorkville district. A respected obstetrician and U.S. Army Reserve officer, Griebl secretly became the Abwehr’s chief coordinator for a sprawling spy network that spanned Boston, Norfolk, and Baltimore.
He recruited engineers with German‑American ties, extracting secret military and defense plans, and even held a ceremonial Luftwaffe captain’s commission. When his associate Guenther Rumrich was arrested in 1938, Rumrich’s confession exposed Griebl’s operation. Griebl was summoned for questioning, offered to name all his contacts, and was released on the promise he would appear before a grand jury.
He vanished instead, boarding a ship back to Hamburg, later resuming his medical practice in Vienna and never again spying for Germany. Griebl remains the only known individual to have held simultaneous commissions in both the U.S. and German militaries.
2 The Shipyard Metallurgist
Gustav Guellich, a German‑born metallurgist, arrived in America in 1932 and was recruited by Dr. Griebl in 1935 while working at the Federal Shipbuilding Co. in Kearny, New Jersey. His position granted him access to classified Navy projects, including gun designs, destroyer blueprints, and specialized ship cables.
Guellich funneled this intelligence to Griebl, who passed it to Germany. His espionage extended to the burgeoning rocket research of Robert H. Goddard; Guellich observed a test launch of the Nell missile in Roswell, New Mexico, and relayed the findings to Berlin, aiding German rocket development.
Following Griebl’s arrest, Guellich was betrayed, apprehended, and, like many in the Duquesne ring, received a relatively light sentence.
1 William Sebold and the Duquesne Spy Ring
Frederick “Fritz” Duquesne, a South African who despised Britain after the Boer Wars, became a German spy during World War I and later naturalized as a U.S. citizen. In New York, he built an extensive espionage network that harvested information from Nazi agents and moles across the country.
Unbeknownst to Duquesne, the German Gestapo and Abwehr tried to recruit William Sebold, a German‑born naturalized American, in 1939. Sebold pretended to cooperate but instead approached the U.S. Consulate in Cologne and offered his services as a double‑agent.
Back in the United States, Sebold helped the FBI establish a surveillance operation against Duquesne’s ring, even transmitting disinformation to the Germans via coded shortwave radio. In December 1941, just days after Pearl Harbor, the FBI arrested 33 members of the Duquesne spy ring, the largest foreign‑intelligence roundup in American history.
While most conspirators were convicted, Sebold’s fate remains a mystery; some speculate he received a new identity for protection. The 1945 film “The House on 92nd Street” dramatized his role.