[[File:Cornelis_Cornelisz._van_Haarlem_-_The_Fall_of_the_Titans_-_Google_Art_Project.jpg|thumb|''[[The Fall of the Titans]]'' (1588–1590)]]
Born in [[Haarlem]], Cornelis Corneliszoon was a pupil of [[Pieter Pietersz]] in Haarlem, and later [[Gillis Coignet]] in [[Antwerp]].
<ref name=RKD>[http://www.rkd.nl/rkddb/dispatcher.aspx?action=search&database=ChoiceArtists&search=priref=18412 Cornelis Cornelisz. van Haarlem] in the [[RKD]]</ref> He is known among art historians as a member of the [[Haarlem Mannerists]], who were highly influenced by the work of [[Bartholomeus Spranger]], whose drawings were brought to Haarlem by [[Carel van Mander]] in 1585, and had a strong immediate effect.<ref name="Slive, 8">Slive, 8</ref> He painted mainly portraits as well as [[mythological]] and [[Biblical]] subjects. Initially Cornelis Cornelisz painted large-size, highly stylized works with Italianate nudes in twisted poses with a grotesque, unnatural anatomy. Later, his style changed to one based on the [[Netherlandish]] realist tradition.
When his parents fled [[Haarlem]] in 1568, as the Spanish army laid siege to the city during the [[Eighty Years' War]], Cornelis Cornelisz remained behind and was raised by the painter [[Pieter Pietersz the Elder]], his first teacher. Later, in 1580-1581 Corneliszoon studied in [[Rouen]], [[France]], and [[Antwerp]] (with Coignet), before returning to Haarlem, where he stayed the rest of his life. He became a respected member of the community and in 1583 he received his first official commission from the city of Haarlem, a militia company portrait, the Banquet of the Haarlem Civic Guard. He later became city painter of Haarlem and received numerous official commissions. As a portrait painter, both of groups and individuals, he was an important influence on Frans Hals. He married Maritgen Arentsdr Deyman, the daughter of a mayor of Haarlem, sometime before 1603. In 1605, he inherited a third of his wealthy father-in-law's estate.