This portrait appears to be a copy after the print made of van Dyck's portrait of Jan van de Wouwer, as part of his Iconographie series. The original painting, which shows the sitter in three-quarter length, is in the Pushkin Museum, Moscow.
According to a letter and photograph from Vose Galleries, the present painting was included in the estate sale of Thomas Gainsborough in 1789, and recorded but not illustrated in E.K. Waterhouse, Gainsborough, London, 1966, p. 124, no. 1019, as Thomas Gainsborough, 'A Portrait'. However, no further documentation has been found to support this information.