Badeau (1831–95) had been the American consul general in London since May 1870, and he remained so until 1881. Born in New York City, he wrote dramatic criticism for the Sunday Times and Noah’s Weekly Messenger, which he collected in 1859 as The Vagabond. In 1862 he enlisted with the Union forces and was made an aide on the staff of General Thomas W. Sherman. Wounded in 1863, he became Ulysses S. Grant’s military secretary in 1864, the beginning of a close friendship that lasted almost until Grant’s death in 1885. In 1868 he published the first of three volumes in his Military History of Ulysses S. Grant (1868–81). In 1869 President Grant appointed him secretary of the legation in London, later raising him to consul general. The quarrel that ended his friendship with Grant concerned Badeau’s role in helping to complete Grant’s memoirs (see N&J3 , 107, 127, 142, 205, 270).

Badeau’s office was in the United States Consulate, at 1 Dunster Court, Mincing Lane. The street address of his home, known as Little Boston House, has not been found (London Directory, 130, 279; Moran, 35:231).