Philip Guedalla (12 March 1889 – 16 December 1944) was a British barrister, and a popular historical and travel writer and biographer. His wit and epigrams are well-known, one example being "Even reviewers read a Preface," another being "History repeats itself. Historians repeat each other." He also was the originator of a now-common theory on Henry James, writing that "The work of Henry James has always seemed divisible by a simple dynastic arrangement into three reigns: James I, James II, and the Old Pretender".
Guedalla was born in Maida Vale, London into a secular Jewish family; in later life he embraced his Jewish identity. He was educated at Rugby School and Balliol College, Oxford, where he in 1911 was the President of the Oxford Union; and was published in Oxford Poetry 1910–1913. In 1919 he married Nellie Maude Reitlinger, the daughter of a banker. They never had children. Asked how to say his name, he told The Literary Digest "My own pronunciation is gwuh-dal'lah. I have very little doubt that this is wholly incorrect."