William Paton Ker, FBA (usually referred to as W. P. Ker; 30 August 1855 – 17 July 1923), was a Scottish literary scholar and essayist.
Born in Glasgow in 1855, Ker studied at Glasgow Academy, the University of Glasgow, and Balliol College, Oxford.
He was appointed to a fellowship at All Souls College, Oxford, in 1879. He became Professor of English Literature and History at the University College of South Wales, Cardiff, in 1883, and moved to University College London as Quain Professor in 1889. However he retained his links with Oxford and was there almost every week during the 1910s, and available to keen students there. He was later the Oxford Professor of Poetry from 1920 to his death, at 67, of a heart attack whilst hill-climbing in Italy. A W. P. Ker Memorial Lecture is held at Glasgow University in his honour.
He is referred to repeatedly in J. R. R. Tolkien's essay Beowulf: The Monsters and the Critics. W. H. Auden's discovery of Ker was a turning point: