This collection of correspondence and papers consists of 32 letters mainly written from Ingram to his mother, and copies of his and his mother's wills; some family photographs and newscuttings. There are a few childhood letters, followed by letters written to his mother from the legations to which he was posted, from Oslo, Berlin, Peking [i.e. Beijing] and Rome. They illustrate the socially exclusive and privileged world of the diplomat in the inter-war years which saw the high-water mark of British foreign and imperial diplomacy. There is a darker tone in the letters written to his mother from the outbreak of war in September 1939. His father had died when he was a child, and his mother was now suffering from poor eyesight and a fading memory, and had been moved to the country, in the company of a nurse. However she was not prepared to accept these new arrangements quietly, demanding repeatedly to return to London. As a result his letters to her became increasingly fraught. In fact, after Ingram's death in May 1941 she returned to London, where she died in January 1943. Ingram bequeathed a number of paintings and Chinese artefacts to the Fitzwilliam Museum in Cambridge.

The correspondence (MS Add.9540/1) has been calendared to provide short summaries of the contents, including some direct quotation. The catalogue has retained original historic language that may be offensive, inaccurate or inappropriate, particularly in regard to descriptions of China, Chinese life and Chinese people. In order to reflect the original context of creation, such historic language has not been edited or replaced.