The diplomat Sir Ernest Satow (1843-1929) left many important papers (diaries and letters) in the Public Record Office (now the UK National Archives). This book is a complete and unabridged collection of his semi-official ('demi-official' in the contemporary jargon) private letters as Her Britannic Majesty's envoy to Japan (1895-1900) and China (1900-1906), with an introduction by noted Foreign Office historian and East Asia expert J.E. Hoare and annotations by Ian Ruxton. These handwritten copies of letters carefully recorded in the author's Letter Books have been transcribed into book form for the first time ever by permission of the National Archives. The aim is to make these valuable documents more easily accessible to scholars and students worldwide.