Frans Hals was a Dutch painter of the Golden Age and is best known for his portraits. Most of them show wealthy citizens, as in 'Portrait of Catharina Hooft and her Nurse' (1619-20) or 'Malle Babbe' (1630), as well as large groups, often featuring civil guards. He studied under Karel van Mander, became a member of the Haarlem Guild of Saint Luke and worked as an art restorer for the city council. After the death of Peter Paul Rubens and Anton van Dyck, he became the most important portraitist in the Netherlands. His portrait of René Descartes in 1649 remains the most famous work of his life. He was a painter who practiced a realistic style: the faces and expressions he captured were not idealized but well distinguishable. He is furthermore distinguished by his fondness for daylight, his free handling of the brush and a silvery sheen on the canvas, although his style subsequently darkened somewhat during his active period.