Sir James Brooke, (1803-1868) entered the army of the East India Company in 1819 but was severely wounded in the first Burmese war and invalided home in 1825. On his return voyage to Bengal on the Castle Huntley in 1830 he befriended John Keith Jolly, one of the ship's officer's, starting a correspondence with him which continued to 1857. Resigning his commission, he sailed on in the Castle Huntley, visiting China, Panang, Malacca and Singapore before returning to England. A second voyage to the East in 1834, however, proved a financial failure.

In 1835 his father died, leaving him a legacy of £30,000 and the means to explore the East Indies. In 1838 he sailed for Borneo with the object of promoting trade and British ascendancy. On his arrival at Singapore the following year, he was asked by the colony's governor to convey thanks and gifts to Rajah Muda Hassim, governor of Sarawak. Brooke accomplished his task and friendly relations were established. On a second visit about a year later, he gave assistance in subduing insurrection. In return he was offered the government and trade of Sarawak, to be held under the sovereignty of Brunei, in return for a small annual payment to its Sultan. In 1841, therefore, he was proclaimed Rajah of Sarawak.

During the late 1840s he befriended Charles Grant, midshipman in HMS Agincourt, taking an interest in his career, appointing him his aide-de-camp and then private secretary. In time, he gathered a group of similar men around him, chiefly from the families of Brooke, Johnson and Grant, all strengthening their ties through inter-marriage. However, it was his nephew, [John] Brooke Brooke that Sir James chose as his heir, proposing in 1845 that he should join him as aide-de-camp.

Brooke eventually left the army and joined the Sarawak Service in 1848. However, during the course of the Rajah's negotiations with the British Government, Holland, France and Belgium, a rift appeared between the two men over Sarawak's ability to maintain her independence unsupported. The differences between them increased after 1858, when Sir James suffered a stroke while in England and Brooke took responsibility for governing Sarawak. The death of his wife and two sons, and the constant letters of instruction and criticism from the Rajah led to a confrontation at Singapore in 1863. Although Brooke submitted to his uncle's authority, he continued to fight for his position, though the publication of his pamphlet A Statement regarding Sarawak (s.l., s.d., s.n.) led to his disinheritance by his uncle. Brooke's brother Charles was installed in his place and in 1868, on the death of Sir James, became 2nd Rajah. Brooke died soon afterwards.

The papers offer first-hand accounts of many contemporary events and developments, including the insurrection of the Chinese gold-workers in 1857, the Muka incident of 1860, relations with the Borneo Company, the suppression of piracy, the conduct of the Borneo Mission and the Commission of Enquiry appointed by the British Government to examine accusations brought against the Rajah by Joseph Hume, MP.