Bernt Wilhelm Westermann (2 October 1781 in Copenhagen – 10 March 1868) was a wealthy Danish businessman who collected insects.
He was based in Slotsholmsgade at the 1850 census (Bag Børsen No.
[1] An amateur insect collector Westermann travelled to Calcutta (India) and later to Jakarta (Indonesia) as an employee of an English business firm.
At the Cape of Good Hope, in Bengal and Java he collected insects for English and Dutch friends, amongst others for Thomas Horsfield.
Insects from all orders acquired and collected during the rest of his life added to his Cape, Java and Bengal insects to form a notable collection.