In 1938, eighteen individuals in the United States were indicted on charges of spying for Nazi Germany. The case resulted in four criminal convictions. The case was named after Guenther Gustave Maria Rumrich, a United States Army sergeant turned deserter who pleaded guilty to espionage and agreed to testify on behalf of the US government. All four individuals served time in prison, with sentences ranging from two to six years. The case was the first major international spy case for the Federal Bureau of Investigation (FBI).