Kenneth Arthur Muir was born in New Cross Road, London, on 5 May 1907. He was educated at Epsom College from 1917 (a boarding school for the sons of doctors) and subsequently read English at St. Edmund Hall, Oxford. He graduated in 1929 and remained to take the Diploma in Education. He began acting in plays at Epsom and continued in Oxford. In 1930 he was appointed to a lectureship at St. John's College, York (Anglican Training College for Teachers): here, he also directed student productions, and joined the York Settlement Community Players (where he directed and acted in various productions).

In 1937, he became a lecturer at Leeds University. During the Second World War he continued lecturing but also did war work, first as an officer in charge of the War Room, North East Regional Control, and then in a Report Centre. He directed for the students' dramatic society, and then the staff dramatic society where he took a series of leading roles. By 1951 he had become a senior lecturer, as well as a city councillor and Chairman of the Leeds City Labour Party and the Leeds Fabian Society (he was a committed Socialist and Labour Party supporter).

He was appointed to the King Alfred Chair of English Literature at the University of Liverpool in 1951, and lived in Birkenhead. He was also Dean of the Faculty of Arts at the university, 1958-61. He retired in 1974.

He married Mary Ewen in 1936: they had a daughter, Katherine (1943) and a son, David (1951). Both his wife and daughter died from leukemia, in 1975 and 1981 respectively.

His first book was a collection of poetry, ‘The Nettle and the Flower’, published in 1933. He published under various pseudonyms, including E. G. Newberry, Louis Cartel and Mark Finney. As well as writing his own poetry, plays and short stories, he was an eminent Shakespearean scholar and critic, editing five of the plays and producing a huge number of books and articles on the plays and poems, he edited ‘Shakespeare Survey’ and served as chairman and president of the International Shakespeare Association. He also published on Thomas Wyatt, Renaissance and Romantic literature, and modern poetry and fiction, and translated various works.

Muir died on 30 Sep 1996.