His father, Robert, (was a member of parliament, Attorney General and, for many years, a full-time judge of the Privy Council) was created the first Lord Monkswell.

[2] John Collier's elder brother, the second Lord Monkswell, was Under-Secretary of State for War and Chairman of the London County Council.

In 1881, the couple settled in Tite Street, Chelsea, in a purpose-built studio house, alongside their friend Anna Lea Merritt.

In 1893, for example, his subjects included Lovelace Stamer, Bishop of Shrewsbury; Sir John Lubbock FRS; A N Hornby (Captain of the Lancashire Eleven); Edward Augustus Inglefield (Admiral and Arctic explorer).

Toole (1887) and Madge Kendal, Ellen Terry and Herbert Beerbohm Tree (in The Merry Wives of Windsor) (1904); heads of educational institutions such as the Master of Balliol Edward Caird (1904), the Warden of Wadham G.E.

[5] A photocopy of John Collier's Sitters Book (made in 1962 from the original in the possession of the artist's son) can be consulted in the Heinz Archive and Library, National Portrait Gallery.

[6] This is the artist's own handwritten record of all his portraits, including name of subject, date, fee charged, and details of any major exhibitions of the picture in question.

His entry in the Dictionary of Art (1996 vol 7, p569), by Geoffrey Ashton, refers to the invisibility of his brush strokes as a "rather unexciting and flat use of paint" but contrasts that with "Collier's strong and surprising sense of colour" which "created a disconcerting verisimilitude in both mood and appearance".

Other pictures may be seen in houses and institutions open to the public: his Clytemnestra, a large and striking painting of the mythical figure, is in the Guildhall Gallery of the City of London.

Another version, in which Clytemnestra has committed the murder and stands half-naked by the bath with a bloody sword is in the Worcester City Art Gallery & Museum.