 Later, his style changed to one based on the Netherlandish realist tradition.When his parents fled Haarlem, as the Spanish army laid siege to the city in 1573 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.