Peter Fenger and Johann Ludvig Zinn both worked for the firm in the beginning of their careers.
In 1754, he purchased the Danish West India Company's buildings and quay at Christianshavn.
He was also involved in the Royal Greenland Trading Department and was in 1755 appointed as director of the Danish Africa Company.
Wewer married his widow, Anna Maria Fabritius née Köster, on 19 January 1748.
His widow married major-general Jean Baptiste Descariéres de Longueville (1699–1766) in 1763.