Frank Steiner was born into a family of Jewish converts to Catholicism in 1922. His father, Richard Steiner (1878-1944), a high court judge, it is thought, had converted as a student for pragmatic reasons. Frank's mother, Paula, who came from an assimilated Jewish background, followed suit. Both Frank and his brother, Willi (1918-2003), were raised in the Catholic faith. Frank was able to come to England on the Kindertransport via the Catholic section of the Refugee Children's Movement. A place had been found for him at Belmont Abbey, a Catholic boarding school in Herefordshire. Meanwhile, his brother, Willi, had already managed to obtain a student visa to study law. He went on to become a distinguished academic lawyer.

Their parents remained in Vienna. They were later misinformed by the American Quakers organisation, which still had offices in Vienna in 1939, that they would be able to obtain transit visas from any neutral country to Britain or the USA so they went to Budapest where they had a number of relatives. Once they discovered that they were unable to obtain further visas, it was thanks largely to the connection through the school that Frank and Willi were able to bring about the extension of their parents's stay in Hungary with the influence of Cardinal Seredi, Prince Primate in Hungary. Although ultimately they were deported to their deaths after the Germans invaded in March 1944. Much of the correspondence in this collection is between Willi and Franz in the UK and their parents in Budapest. Between February 1940 and the date Hungary entered the war the boys could correspond with their parents via Switzerland. After that the same route was used through Paula Steiner's uncle, Julian Halberstam (1879-1958), but the post was censored.

Frank was released from internment on his 19th birthday after being found unfit for Army service. Thereafter he worked at a part time office job including civil defence (classed as war work) while reading part time for a London economics degree as an  external student, B .Sc . (Econ)  June 1944; then as a researcher for the Fabian  Society from summer 1944 to spring 1945; then Assistant Principal, Board of Trade May 1945 - summer 1949 (for the first three years in London  for the last six months or so in Paris on  secondment to the newly formed secretariat of the then new OEEC. Eventually Frank ended up working for stock broking firms until retirement. In addition Frank was a correspondent for the Catholic Press Agency 1955-2007. He also sat on the Parliamentary and Public Affairs Committee, Catholic Union of Great Britain, (chair 2000 - 2003). He was made Knight of the Papal Order of St. Gregory,  2003.