Nathaniel Charles Jacob Rothschild was born on 29 April 1936 in Cambridge, England. He was the eldest son of Nathaniel Victor Rothschild, 3rd Baron Rothschild, and Barbara Judith Rothschild, née Hutchinson.
He belonged to the British branch of the Rothschild family, descended from Nathan Mayer Rothschild, who established the family's London banking business in the early nineteenth century.
Jacob grew up during a period of enormous political and economic change. His childhood and youth were shaped by the Second World War, the reconstruction of Britain and the transformation of the British financial system.
After Eton and Oxford, he entered the family banking business. He joined N M Rothschild & Sons in 1959 and became a partner in 1963. During this period, he worked alongside other members of the family, including Sir Evelyn de Rothschild.
However, Jacob eventually decided to pursue a different direction. In 1980, he left N M Rothschild & Sons and took independent control of the Rothschild Investment Trust, which he developed into what became RIT Capital Partners.
Under his leadership, RIT grew substantially. According to RIT Capital Partners, when Jacob retired from its board in 2019, the company's net asset value had increased from approximately £5 million to more than £3 billion, and the company had become listed on the London Stock Exchange.
Jacob's business interests expanded beyond investment management. In 1991, he co-founded J. Rothschild Assurance Group with Sir Mark Weinberg, which subsequently became St. James's Place plc. He also became involved in media, energy, property and international investment.
At the same time, he developed a remarkable second career as a philanthropist and supporter of the arts and heritage.
He was chairman of the National Gallery from 1985 to 1991 and chairman of the National Heritage Memorial Fund from 1992 to 1998. He subsequently chaired the Heritage Lottery Fund, overseeing the distribution of approximately £1.2 billion in grants to heritage projects.
He also became deeply associated with Waddesdon Manor, the Rothschild family's historic estate in Buckinghamshire. After inheriting the estate from his cousin Dorothy de Rothschild in 1988, he helped oversee its restoration and development in cooperation with the National Trust.
Jacob died on 26 February 2024. His only son, Nathaniel Philip Victor James Rothschild (Nat Rothschild), subsequently became the 5th Baron Rothschild.