"James Evershed Agate" was a British diarist and critic. In the period between the wars, he was one of Britain's most influential theatre critics. After working in his father's business until his late twenties he found his way into journalism, being on the staff of The Guardian/The Manchester Guardian (1907–14); drama critic for Saturday Review (London)/The Saturday Review (1921–23), and The Sunday Times (UK)/The Sunday Times (1923–47), and holding the same post for the BBC (1925–32).
Agate's diaries and letters, published in a series of nine volumes under the title of Ego, are a record of the British theatre of his era and also of his non-theatrical interests, including sports, social gossip and his private preoccupations with his health and precarious finances. In addition to drama criticism he wrote about the cinema and English literature for London newspapers, and published three novels, translated a play and had it staged in London, albeit briefly, and regularly brought out collections of his theatre essays and reviews.More James Agate on Wikipedia.