Sir John Knewstub Maurice Rothenstein CBE (1901–1992) was an English art historian. He grew up in London the son of Sir William Rothenstein. The family was connected to the Bloomsbury Set. John Rothenstein studied at Oxford University and became friends with T. E. Lawrence.

From 1938 to 1964 he was director of the Tate Gallery. Rothenstein's directorship — the longest to date — was a period of relative stagnation for the gallery as there were few major bequests or expansions of the building. The Tate's annual purchase fund could not compete with US institutions so few works of modern foreign art were added to the collection. Rothenstein was publicly dismissive of the influence of the School of Paris stating that Picasso was over-rated and had been a critic of the Vorticists. According to Richard Cork one of Rothenstein's major errors was failing to purchase 'The Red Studio' a major work by Henri Matisse when it was offered to the Tate Gallery for a few hundred pounds in 1941. The art dealer Douglas Cooper began an open campaign to have Rothenstein dismissed by the trustees leading to an incident in which Rothenstein punched Cooper in the face. In any context Rothenstein's stewardship and preservation of the collection during the war years was a major accomplishment. The Tate also began to host temporary exhibitions during this period organised by the Arts Council of Great Britain including a major retrospective of Picasso.

Rothenstein was knighted on 1 January 1952.

[edit Works

• Modern English Painters, 1952-74
• Autobiography, 1965, 1966