Nicholas "Nick" Dozenberg (1882–1954) was an American political functionary with the Communist Party USA in the 1920s. Late in 1927 Dozenberg was recruited into the underground Soviet military intelligence network, for which he worked for more than a decade under the pseudonym "Nicholas Ludwig Dallant." Apprehended by the Federal Bureau of Investigation in December 1939, Dozenberg cooperated with the investigation fully, giving oral or written testimony before the House Committee on Un-American Activities (HUAC) on three separate occasions. Never charged for espionage, Dozenberg pleaded guilty to a charge of passport fraud in 1940 and received a comparatively light jail term of one year and one day. He lived a quiet and private life following his release from prison in 1941.
Nicholas Dozenberg was born November 15, 1882 in Riga, Russian Empire, today the capital of Latvia, the son of a farmer. He attended school in the town of Talsi.
Dozenberg emigrated to the United States in 1904, settling in the Boston suburb of Roxbury, Massachusetts, center of a large Latvian community. He worked there in a plant making artificial marble, in an iron foundry and, during 1906 -1919 period, as a railroad locomotive machinist. He was a member of the International Association of Machinists from 1908 and the treasurer of IAM Lodge 391 in 1917 and its president in 1918.
Dozenburg was naturalized as an American citizen in the United States District Court at Boston in February 1911.