Dutch painter of pastoral landscapes in the Italianate manner, principally active in Haarlem. He was the son of the still-life painter Pieter Claesz. and it is not known why he adopted a different surname. Claesz. was his first teacher, but although Berchem tried his hand at most subjects, no still-lifes by him are known. He visited Italy in the 1640s and perhaps again in the 1650s and became, with Jan Both, the most highly regarded exponent of the Italianate landscape. Successful and well rewarded in his lifetime, he had numerous pupils and his influence on 18th century English and French landscape painters was very considerable, Gainsborough and Watteau being among the artists who particularly admired his work. //