Little is known about Hayls (or Hales). He trained in The Hague or Amsterdam under the portraitist Miereveldt, and is recorded as being in Rome in 1651. He was active as a portraitist in the 1650s and 1660s, and in 1658 is listed by the British writer Sanderson as among the most important portrait painters in England. A contemporary of Sir Peter Lely and a cousin, probably by marriage, of the miniaturist Samuel Cooper, Hayls is frequently mentioned in Pepys's Diary. Pepys commissioned Hayls to paint a portrait of his wife as St Catherine in 1666 (now lost) and, pleased with the result, ordered a portrait of himself as well (National Portrait Gallery) for the then large sum of 6314.
The artist lived in London, apparently in some affluence, moving by 1668 from Southampton Street to Long Acre, near his cousin Cooper. One of three painters under consideration in 1670 to paint the series of Justices for the Guildhall, he lost the commission to John Michael Wright. The diarist George Vertue records that he 'dyd at his house in long Acre. comeing from the necessary house he dropt down dead in the Garden. being drest in a velvet suit to go to a Ld Mayors feast' ('Vertue Note Books, I', Walpole Society, XVIII, Oxford 1930, p.31). He was buried at St Martin-in-the-Fields church.
Mary Edmond, 'Limners and Picturemakers', Walpole Society, XLVII, London 1980, pp.106-7, 111
Jane Turner (ed.), The Dictionary of Art, London and New York 1996, XIV, pp.268-9
Ellis Waterhouse, Painting in Britain 1530 to 1790, New Haven and London, 1994 edition, pp.100-1, 108, 342-3 (ch.6, n.11)