Gerard Soest was born of unknown parents in Soest, Westphalia, in the early part of the first decade of the seventeenth century, circa 1601/1602 (he was noted by Charles Beale as "neare 80 years old when he died"). Nothing certain is known of his training or of his work in Holland, but his later style suggests links with the Utrecht school.
Soest may have come to London as early as 1644 and was certainly there by 1650. His studio was first near Lincoln's Inn Fields, then in Southampton Buildings, north of the Strand. He never attained the status or the vogue of Lely and seems never to have painted at court. He was evidently temperamently unsuited to the establishment of an effective studio, and was unpopular with fashionable female clients. His work was chiefly on a head-and-shoulders scale; otherwise he seems to have specialized in three-quarter-length portraits, full lengths being less common. His portraits were generally of male sitters. Soest also painted allegorical works, in some of which he indulged his taste for the erotic. He died in London on 11 February 1681.
[Hayes, John. British Paintings of the Sixteenth through Nineteenth Centuries. The Collections of the National Gallery of Art Systematic Catalogue. Washington, D.C., 1992: 254.]