The papers cover the whole span of Brooke rule in Sarawak; looking back to Thomas Brooke, father of Sir James, the first Rajah, and forward to the present day. Sir James Brooke ruled Sarawak from 1841 until his death in 1868. Although he had initially planned to make his nephew, John Brooke Brooke, his heir and second Rajah, a rift developed between them over Sarawak's ability to maintain its independence unsupported. This resulted in the passing of the title to another nephew, Charles Anthony Johnson Brooke, whose wife was the Ranee, Margaret. Charles Brooke died in 1917 and was succeeded by Sir Charles Vyner Brooke, the third Rajah.

Sir Charles Vyner Brooke married Sylvia Brett (the Ranee Sylvia) in 1911 and had three daughters: Elizabeth Vidmer, Valerie Memery Wyatt, and Leonora Tompkins. He oversaw the Cession of Sarawak to the British Crown in 1946, with which the greater part of the papers is concerned. His executor was Mrs Evelyn Hussey, who had been his secretary in London from 1946 until his death in 1963. Lord Tanlaw, formerly Simon Mackay, is Charles Vyner Brooke's grandson (the son of Leonora Tompkins).

Charles Vyner Brooke's brother, Bertram, the Tuan Muda (heir-presumptive), married Gladys Palmer and had four children: Elizabeth Maunsell, Lady Jean Halsey, Lady Anne Bryant, and Anthony Brooke. Until 1946, Anthony Brooke had been the Rajah Muda (heir-apparent). He married Kathleen Mary Hudden (1907-1981) in 1939, who went on to play an important part in the anti-Cession campaign fought by Anthony, Bertram, and loyalist Malayan (Malaysian) and Dayak communities. When the new colonial Government of Sarawak refused Anthony Brooke permission to enter the state in Nov 1946, she made an extended visit in his place. Meanwhile, Anthony and Bertram led a campaign of letters and articles in England and pursued civil litigation against the third Rajah in the court of Brunei.

Anthony Brooke initiated a ten-year span of correspondence with Dame Margery Perham in 1939, which is also represented in the papers. After stepping back from the anti-Cession campaign in 1951, he went on to travel the world campaigning for peace and international understanding. Kathleen Brooke, during the last years of her life, planned to write a memoir of her involvement in the Cession for her three children, and the collection includes papers selected with this object in view.

The Brookes were joined in the anti-Cession campaign by their close family friend, Mrs Margaret Noble, who also researched Brooke family genealogy. A large part of the collection was deposited by Margaret Noble and includes her own papers.

Many thanks are extended to Mrs Noble for help and information generously given, as well as to Professor Robert Reece, author of The Cession of Sarawak to the British Crown in 1946, who, through personal contacts made during the course of his research, was responsible for many additions to the collection.