Olschanezky was born in Chemnitz, Germany, in 1923. Her parents were secular Jews, her father a Russian-born chemical engineer and her mother from a moneyed German family.
They were unable to return to Russia following the First World War and settled in Chemnitz. Sonia was the youngest of their three children and three years after her birth, the family moved to Bucharest where her father managed a successful silk stocking factory. The rise of anti-Semitism saw her father being swindled and the family moved again, this time to France.
The rise of anti-Semitism saw her father being swindled and the family moved again, this time to France, but her father was again defrauded and the family fell into poverty.
At the age of ten, Olschanezky joined a theatre dance company planning to become a professional dancer to help the family fortunes. She was small, slight and graceful and she might have succeeded in her ambition had not the war intervened.
Following the fall of France, Olschanezky joined the resistance at Châlons-sur-Marne and spent her time carrying messages between the resistance and agents of the British Special Operations Executive (SOE).
The French authorities cooperated with the persecution of the Jews and in 1942 Olschanezky was arrested and detained at a camp at Dransy prior to being sent to one of the extermination camps in the east. Fortunately, her mother was able to contact friends in Germany who produced papers that stated that Olschanezky had ‘economically valuable skills’ for the war effort and she was released.
Olschanezky returned to her resistance work with her fiancé, Jacques Well, as part the Juggler sub-circuit of the Physician Network, and in 1943 she learnt of the capture of Noor Inayat Khan, who I’ve written about previously. She warned London that Khan’s radio was now in the hands of the enemy, but her warning was considered unreliable as Olschanezky was one of the few operatives who hadn’t been trained by the SOE. As a result, agents continued to be sent to France and were captured.
The network was betrayed and most of its leaders arrested, but Olschanezky remained free until she herself was captured in 1944. She was interrogated by the Gestapo before being transported with other SOE agents to the concentration camp at Natzweiler-Struthof. That same day, she was injected with Phenol and her body cremated. She was just twenty years old.
Olschanezky is commemorated with a plaque at the Allied Special Forces Memorial Grove at the National Memorial Arboretum in Staffordshire.