Lady Mairi Bury of Mount Stewart in County Down has died at the age of 88.
Lady Mairi, daughter of the 7th Marquess of Londonderry, died at Mount Stewart on Monday.
The Londonderrys were a highly influential aristocratic family in the early 20th century. Visitors to the family seat outside Newtownards included prime ministers and royalty.
However, the most infamous of visitors was Hitler's foreign minister von Ribbentrop who spent four days at the Strangford Lough estate in 1936.
Von Ribbentrop was brought to Mount Stewart by Lady Mairi's father, the then Lord Londonderry.
A controversial figure, he had been minister for education in Northern Ireland in the 1920s before leaving the political scene here in frustration after his attempts to create a secular, non sectarian school system stalled.
In the 1930s he was air minister in the national government, and while he encouraged friendship with Germany he was also responsible for building up the RAF at a time of growing anti-war sentiment in the United Kingdom.
It was under this shadow that Lady Mairi grew up.
"Among the Londonderry archives there is actually a letter from Adolf Hitler to Lady Londonderry thanking her for beautiful Irish roses," said historian Dr Eamon Phoenix.
"By the time he (Lord Londonderry) died in 1949, he was being traduced in the press as a friend of Nazi gangsters. A photograph of him with Hitler and Ribbentrop in Berlin in 1936 was published in the media."
But Lady Mairi's world was also one of balls at Buckingham Palace and famous faces.
Born at Mount Stewart in 1921, she lived there most of her life.
At the age of 16 she came out into London society was presented to King George VI and Queen Elizabeth.
"She grew up with the glitterati," continued Dr Phoenix.
"People like the playwright Sean O'Casey and Labour politician Ramsey McDonald were all part of the Ark Club her mother presided over at Mount Stewart."
In 1940 Lady Mairi married Derek William Charles Keppel, Viscount Bury. They divorced in 1958.
The National Trust took over the gardens in 1957, and in 1977 Lady Mairi entrusted them with the house and most of its contents.
"She had a sense of public service and conducted tours of the estate into her old age, talking to ordinary people about the big house and the problems maintaining it," said Dr Phoenix
"She came from another age."
Towards the end of her life Lady Mairi broke away from the official Ulster Unionism of her forefathers and became a public supporter of the DUP.
In a statement DUP Leader and First Minister Peter Robinson paid tribute to a "remarkable woman".
"In opening Mount Stewart to the public she gifted to the people of Northern Ireland a beautiful and much loved attraction which is enjoyed by hundreds of thousands every year," he said.
Lady Mairi is survived by her two daughters Elizabeth and Rose, three grandchildren and three great grandchildren.
The private funeral of Lady Mairi will be held at Mount Stewart on Thursday. A public memorial service will be held at St mark's parish Church, Newtownards in the New Year.
The house and gardens at Mount Stewart will be closed on Thursday 19 November.