Jane Haining, a Church of Scotland missionary, died in the Auschwitz-Birkenau concentration and extermination camp in 1944, aged 47.
An informer told the Gestapo that Miss Haining, a matron at the Scottish Mission School in Budapest, Hungary, was providing cover for Jewish pupils in her care.
Miss Haining, from Dunscore in Dumfries and Galloway, was officially honoured at the Yad Vashem memorial in Israel.
Her will was discovered in a box at the Kirk’s World Mission Council’s archive in Edinburgh earlier this year.
The Moderator of the General Assembly, Right Rev Dr Russell Barr, hosted a reception in Edinburgh at which 14 of Miss Haining’s relatives were brought together – some meeting for the first time.
For Joyce Greenlees, 59, from Cumbernauld, North Lanarkshire, one of the relatives attending the ceremony met the children and grandchildren of the missionary’s late half-sister Agnes O’Brien, for the first time.
Mrs Greenlees, whose grandfather Harold Haining was Miss Haining’s cousin, only learned she had family links in Northern Ireland, Belgium and England after reading about the discovery of the will.
“I am so proud and pleased to meet members of a family I did not realise existed. Jane Haining was a very brave lady who was totally selfless, and I think it is very important that everyone knows her story because we can learn lessons from the fact she deeply cared about all people, regardless of religious belief,” she said.
Caitriona Topping, 24, whose grandmother was Ms O’Brien, said she felt her connection with Miss Haining had been deepened after holding her will.
An avid listener of BBC radio, Miss Haining was aware of the growing threat the Nazis posed to the Hungarian Jews in the 1940s.
She was repeatedly ordered by church officials to return to Scotland, but refused, writing: “If these children need me in days of sunshine, how much more do they need me in days of darkness.”
Dr Barr said: “Jane’s story is one of the most remarkable stories of courage and loyalty.
“There was something quite special about seeing her family holding the various photographs and letters and to feel their immense sense of pride in what Jane did and in the ways in which her life and death have now been recognised.”
The Gestapo charged Miss Haining with working amongst Jews, listening to news broadcasts on the BBC and sending British prisoners of war parcels