Cornelis de Graeff, also Cornelis de Graeff van was the most memorable member of the De Graeff family. He was a mayor of Amsterdam from the Dutch Golden Age and a powerful Amsterdam regent after the sudden death of stadholder William II of Orange. Like his father Jacob Dircksz de Graeff, he opposed the house of Orange, and was the reasonable successor to the republican Andries Bicker. In the mid 17th century he controlled the city's finances and politics and, in close cooperation with his brother Andries de Graeff and their nephew Johan de Witt, the Netherlands political system.
Characteristic of his early period, from about 1646 to 1655, is the choice of very effortless motifs and the careful and laborious study of the details of nature. The time between his disappearance from Haarlem and his settling in Amsterdam may have been spent in travelling and helped him to gain a broader view of nature and to widen the horizon of his art.
A magnificent view of the Castle of Bentheim, dated 1654, suggests that his wanderings extended to Germany. In his last period, from about 1675 onwards, he shows a tendency towards overcrowded compositions, and affects a darker tonality, which may partly be due to the use of thin paint on a dark ground. Towards the end, in his leaning towards the romantic mood, he preferred to draw his inspiration from other masters, instead of going to nature direct, his favorite subjects being rushing torrents and waterfalls, and ruined castles on mountain crests, which are frequently borrowed from the Swiss views by Roghmau.