Pieter Cramer (21 May 1721 (baptized) – 28 September 1776), was a wealthy Dutch merchant in linen and Spanish wool, remembered as an entomologist. Cramer was the director of the Zealand Society, a scientific society located in Flushing, and a member of Concordia et Libertate, based in Amsterdam. This literary and patriotic society, where Cramer gave lectures on minerals, commissioned and/or financed the publishing of his book De uitlandsche Kapellen, on foreign (exotic) butterflies, occurring in three parts of the world Asia, Africa and America.
Cramer assembled an extensive natural history collection that included seashells, petrifications, and insects of all orders. Many were colourful butterflies and moths (Lepidoptera), collected in countries where the Dutch had colonial or trading links, such as Surinam, Ceylon, Sierra Leone and the Dutch East Indies.
Cramer decided to get a permanent record of his collection and so engaged the painter Gerrit Wartenaar to draw his specimens. He also arranged for Wartenaar to draw butterflies and moths belonging to other keen Lepidoptera collectors in the Netherlands. One of them was stadtholder-prince William V of Orange. Hans Willem Baron Rengers and Joan Raye, the son of the former governor in Surinam, were among the others. Such was the quality of the illustrations that Caspar Stoll encouraged him to publish the set of drawings.