A native of Germany,
William Sebold served in the German army during World War I. After leaving
Germany in 1921, he worked in industrial and aircraft plants throughout the
United States and South America. On February 10, 1936, he became a naturalized
citizen of the United States.
Sebold returned to
Germany in February, 1939, to visit his mother in Mulheim. Upon his arrival in
Hamburg, Germany, he was approached by a member of the Gestapo who said that
Sebold would be contacted in the near future. Sebold proceeded to Mulheim where
he obtained employment.
In September, 1939, a Dr.
Gassner visited Sebold in Mulheim and interrogated him regarding military planes
and equipment in the United States. He also asked Sebold to return to the United
States as an espionage agent for Germany. Subsequent visits by Dr. Gassner and a
"Dr. Renken," later identified as Major Nickolaus Ritter of the German Secret
Service, persuaded Sebold to cooperate with the Reich because he feared
reprisals against family members still living in Germany.
Since Sebold's passport
has been stolen shortly after his first visit from Dr. Gassner, Sebold went to
the American Consulate in Cologne, Germany, to obtain a new one. While doing so,
Sebold secretly told personnel of the American Consulate about his future role
as a German agent and expressed his wish to cooperate with the FBI upon his
return to America. Sebold reported to Hamburg, Germany, where he was instructed
in such areas as preparing coded messages and microphotographs. Upon completion
of training, he was given five microphotographs containing instructions for
preparing a code and detailing the type of information he was to transmit to
Germany from the United States. Sebold was told to retain two of the
microphotographs and to deliver the other three to German operatives in the
United States. After receiving final instructions, including using the assumed
name of "Harry Sawyer," he sailed from Genoa, Italy, and arrived in New York
City on February 8, 1940.
The FBI previously had
been advised of Sebold's expected arrival, his mission, and his intentions to
assist them in identifying German agents in the United States. Under the
guidance of Special Agents, Sebold established residence in New York City as
Harry Sawyer. Also, an office was established for him as a consultant diesel
engineer, to be used as a cover in establishing contacts with members of the spy
ring. In selecting the office for Sebold, FBI Agents ensured that they could
observe any meetings taking place there.
In May, 1940, a shortwave
radio-transmitting station operated by FBI Agents on Long Island established
contact with the German Shortwave station abroad. This radio station served as a
main channel of communication between German spies in New York City and their
superiors in Germany for 16 months. During this time, the FBI's radio station
transmitted over 300 messages to Germany, and received 200 messages from
Sebold's success as a
counterespionage agent against Nazi spies in the United States is demonstrated
by the successful prosecution of the 33 German agents in New York. Of those
arrested on the charge of espionage, 19 pleaded guilty. The 14 men who entered
pleas of not guilty were brought to trial in Federal District Court, Brooklyn,
New York, on September 3, 1941; and they were all found guilty by jury of
December 13, 1941.
Click on the members
photo for more information on the activities of each of these convicted spies
and Sebold's role in uncovering their espionage activities for the Reich.