Thomas de Keyser, son of the sculptor and architect Hendrick de Keyser, was born in Amsterdam around 1596/97. After Thomas completed an apprenticeship with an unknown painter, possibly Cornelis van der Voort, his father introduced him to the fundamentals of architecture from 1616 to 1618. He nevertheless turned to painting again, specialising in portraits. On 5 July 1626 De Keyser married Machtelt Andries, from a wealthy family of goldsmiths, with whom he had four children. His artistic renown is documented by official commissions, among them a militia painting with the company of Captain Allaert Cloeck and Lieutenant Lucas Jacobsz. Rotgans, which was completed in 1632 (Amsterdam, Rijksmuseum). In the 1640s De Keyser increasingly turned to other sources of income: like his brother Pieter, he began dealing in building materials and maintained mercantile connections as far away as London. Even so, he continued to paint, though to a lesser extent, and in 1652 he was commissioned with the large-format history painting 'Odysseus and Nausicaa,' which was to grace Amsterdam's 'stadhuis'. On 7 June 1667 the painter was buried in Amsterdam. With his novel small-format likenesses, which pictured the subject in full figure in a frequently highly detailed interior, De Keyser developed a new portrait type. For this, he borrowed from the small-format genre scenes painted by Willem Duyster and Pieter Codde, which are often set in interiors. In the last years of his life, De Keyser became an important exponent of the equestrian portrait in Holland.