The portraiture of Fra' Galgario, which combined the historical naturalistic tradition of Lombardy and the renewed interest in the legacy of Rembrandt, brought the genre in Northern Italy to a new level of expression. His masterful technique was allied with an inherent capacity for capturing his sitters that went well beyond their external appearance.
Fra' Galgario's paintings entered the most important European collections, notably that created by Field Marshal Count Johann Matthias von der Schulenburg, who bought eleven canvases by the artist in 1711. From 1732, the artist reached the apex of an extraordinary artistic development when he started to paint with his finger: 'cominciò a dipignere col dito anulare tutte le carnagioni, la qual cosa continuo sino alla morte ... né mai più, nel far le sole carnagioni però, si servì di pennello, se non in qualche minuta parte, o per dare gli ultimi colpi; ed in questa sua maniera ha fatto bellissime teste, e pastose quant'altre mai, tuttoché fatte a tocchi interamente' (F.M. Tassi, Fra Vittore Ghislandi pittore, in Vite de' pittori scultori e architetti bergamaschi, Bergamo, 1793, II, p. 68).
Throughout the 17th century artists became increasingly interested in their own image, often for the purposes of creating a celebrated likeness that could reflect and in turn enhance their social status, and to provide an image for posterity (that could be printed in their biographies and included in galleries of artist's portraits). Fra' Galgario left several splendid self-portraits, dated between 1710 and 1737. He also painted several portraits of other artists, including the Portrait of a young painter in Cologne, Wallraff-Richartz Museum-Fondation Corboud.