Thomas de Keyser was, with Nicolas Eliasz., the most popular portrait painter in Amsterdam until the arrival of
Rembrandt in 1631/2. He specialised in small-scale portraits notable for their meticulous finish and attention to detail, as well as life-size portraits.
Thomas de Keyser was the son of the famous Amsterdam architect and sculptor, Hendrick de Keyser (1565 - 1621), who trained him.
His earliest dated work is a group portrait of Amsterdam Surgeons (Amsterdam, Rijksmuseum), painted in 1619. Further group portraits followed, as well as his small-scale individual portraits.
After 1640 he became active as a stone merchant and his output of paintings declined.