British politician, author, and social activist Arthur Augustus William Harry Ponsonby, 1st Baron Ponsonby of Shulbrede (16 February 1871 - 23 March 1946). He was the son of Mary Elizabeth Bulteel, the daughter of John Crocker Bulteel, and Sir Henry Ponsonby, the private secretary to Queen Victoria. In addition, he was the great-grandson of the second Earl Grey, the third Earl of Bathurst, and the third Earl of Bessborough. His elder brother was 1st Baron Sysonby. "When war is declared, truth is the first casualty" is a quotation that is frequently attributed to Ponsonby. It was published in his book Falsehood in War-time, containing an Assortment of Lies Circulated Throughout the Nations During the Great War (1928). But at the beginning of the book, he presents this phrase-which is enclosed in quotation marks-as an epigram rather than using it himself. The nearly exact same statement made by US Senator Hiram Johnson in 1917-"The first casualty when war comes is truth"-is most likely its source. From 1882 until 1887, Ponsonby served as Queen Victoria's Page of Honour. He was raised in an Anglo-Irish household and attended Eton College.
