A handwritten will and previously unpublished photographs give a fascinating insight into the life of Jane Haining, who died at Auschwitz in 1944.
The 47-year-old refused to abandon Jewish girls in her care -- many of whom were orphans -- when she was a matron at the Jewish Mission School run by the Scottish Mission in Budapest, Hungary.
She protected 315 students at the school for four long years before finally being betrayed, which led to her arrest by the Gestapo.
Before her arrest, Haining had been urged to return to Scotland. But she refused, declaring "I shall continue to do my duty," according to the documents.
"If these children need me in days of sunshine, how much more do they need me in days of darkness."
The new material, which will soon be handed over to the National Library of Scotland, was recently rediscovered in a box in the World Mission Council's archive at the church offices in Edinburgh.
One document is an extract from a report delivered by Polish Bishop Laszlo Ravasz in 1945 -- a year after Haining died at Auschwitz.
It explains that she had three times been ordered by her superiors to abandon the girls and return home.
According to the bishop -- a member of the Reformed Church who also helped to save Jews -- Haining always replied: "I shall continue to do my duty and stick to my post."
Despite being under surveillance, Haining, a farmer's daughter from Dunscore in Dumfriesshire, went to a market at 5 a.m. most days to buy food for the girls.
She also cut up her leather luggage to make soles for their worn-out shoes.
She was finally betrayed by the cook's son-in-law, whom she caught eating scarce food intended for the girls.
Haining was arrested by two officers from the Nazi secret police and charged with eight offenses including "working among the Jews," "weeping when seeing the girls wearing yellow stars," "listening to news broadcasts on the BBC," and "visiting British prisoners of war," according to a post on the Church of Scotland's Facebook page.
She was sent to Auschwitz in Nazi-controlled Poland -- the same camp as some of her students -- where she died of "cachexia (wasting of the body) following intestinal catarrh," according to her death certificate.
The documents were discovered by chance in an attic at the archives in Edinburgh by researchers who were preparing for an exhibition in Budapest marking the 175th anniversary this weekend of the Church of Scotland Mission being founded there.
In a post on the Church of Scotland's Facebook page, Reverend Ian Alexander, Secretary of the Church of Scotland World Mission Council, said: "The most poignant discovery is her last will and testament which says 'to be opened in the event of my death' and dated July, 1942.
"She lays out what her legacies are to be and who is to receive her wireless, typewriter, fur coat and watches.
"It is a wonderful document and tremendously exciting to have something that Jane Haining herself has written. It gives a sense she was fully aware of the risks she was taking."