It is believed that Thomas Hardy wrote much of his novel Jude the Obscure in this pub. In the novel, the city of Christminster is a thinly-disguised Oxford, and it is thought that a pub that appears in certain passages of the novel is based on The Lamb & Flag. The pub also featured frequently in episodes of the ITV detective drama Inspector Morse. The Inklings (a literary group including J. R. R. Tolkien and C.S. Lewis) also met here, although they are more commonly associated with the Eagle and Child, which also stands on St. Giles, directly opposite the Lamb & Flag.
The pub is a favoured location of Oxford students and lies just north of St John's College, who manage it. The Lamb & Flag Passage runs through the south side of the building, connecting St Giles' with Museum Road, where there is an entrance to Keble College to the rear of the pub.
Since the college took over the management of the pub in 1997, a Lamb & Flag scholarship has been instituted for graduate students.
The name of the pub comes from the symbol of Christ as the victorious Lamb of God (Agnus Dei) of the Book of Revelation, carrying a banner with a cross, and often gashed in the side.