Dantsig Sergeevich Baldaev (Данциг Сергеевич Балдаев, 1925–2005) was a Russian Buryat soldier, prison officer, folklorist, illustrator, and author of books on forensic science. English-language sources usually render his given name as Danzig.

He is known for researching the symbolic language of prison tattoos used by Russia's underworld of career criminals for nearly half a century.

Dantsig Baldaev's father was Sergey Baldaev [ru] (Сергей Петрович Балдаев, 1889–1979) an ethnologist and folklorist studying the Buryat language. His family moved to Moscow in 1930.

In 1935 Dantsig's mother died, and in 1938 his father Sergey was branded an "enemy of the people" and arrested by the NKVD. Dantsig was sent to an orphanage for the children of political prisoners near Tulun for two years. Sergey somehow survived and was eventually released. According to Sergey, 58 family relatives were murdered by the NKVD.^[1]

In January of 1943, Dantsig was drafted into the Red Army and deployed to the Manchukuo border. After the war in 1948, fearing Sergey would be arrested again, the two moved to Leningrad. In 1951, Dantsig became a guard at Leningrad's infamous Kresty Prison. Later in life, Dantsig claimed that the had been dragooned into working there by the NKVD.^[2] He continued to work in the MVD prison system for the remainder of his career.

Because his father had once been denounced, Dantsig was relegated to "menial jobs" for the MVD even after the downfall of the NKVD in the early 1950s.^[1] After many years, he gradually rose to the rank of polkovnik.

Dantsig made many illustrations of the atrocities and sadistic torture endemic to the Gulag network.^[2]