These newly-weds have dressed up for their wedding photo but they’re not smiling…

And for good reason: their union was sealed at Auschwitz – the only wedding known to have taken place in the death camp. Rudolf Friemel, an Austrian communist who resisted the Nazis, met his Spanish wife Margarita Ferrer Rey in Spain after going there to fight with the International Brigades in 1936 against General Franco’s fascists during the Spanish Civil War.

He was sent to Auschwitz in 1942 after returning home. Margarita was allowed to travel to Auschwitz from Vienna for the wedding with their son – who was born in 1941 – and Friemel’s father. The marriage was registered at 11am on March 18, 1944, as the slaughter at the camp reached its peak. Friemel was allowed to wear civilian clothes and let his hair grow for the occasion, and a cell was made available to the couple for their wedding night in the camp brothel. But their happiness was short-lived.

Rudolf Friemel was hanged in December 1944 for helping to organise an escape attempt. The camp was liberated a month later. All his wife and child – who moved to France after the war – were left with were his heartbreaking letters and poems. Margarita died in 1987.