From Wikipedia :
Philip Walsingham Sergeant (27 January 1872, Notting Hill, London – 20 October 1952) was a British professional writer on chess and popular historical subjects. He collaborated on the fifth (1933), sixth (1939), and seventh (1946) editions of Modern Chess Openings, an important reference work on the chess openings. He also wrote biographical game collections of Paul Morphy (Morphy’s Games of Chess (1916) and Morphy Gleanings), Rudolf Charousek (Charousek’s Games of Chess (1919)), and Harry Nelson Pillsbury (Pillsbury’s Chess Career, with W. H. Watts, 1922), and other important books such as A Century of British Chess (1934) and Championship Chess (1938).
Harry Golombek writes that, “Without any pretensions to mastership, he represented Oxford University in the years 1892-5”. Golombek considers A Century of British Chess probably Sergeant’s best chess book, but opines that although Sergeant’s chess books are lucidly written, they suffer from the defect that, as a non-master, he was not competent to deal with the annotational aspect of his work.
He was a second cousin of Edward Guthlac Sergeant.