A year after the war ended in 1646, De Geer organized a Swedish trading expedition to Africa. The following year the expedition returned to Sweden, bringing home sugar, gold, ivory and enslaved Africans, which had been purchased from the Gold Coast; De Geer gifted four enslaved Africans to Oxenstierna. After De Geer's monopoly on the Swedish copper trade expired in 1648, he founded the Swedish Africa Company the next year, which led outraged citizens in Amsterdam to riot. The company was founded to engage in the triangular trade and traded in plate copper, iron, gold, ivory, slaves, tobacco, sugar, silver and salt, representing Sweden's first foray into the Atlantic slave trade. In 1650, an expedition by slave trader Hendrik Carloff on behalf of the company founded the Swedish Gold Coast to conduct trade with local African kingdoms. In 1652, De Geer fell ill during a voyage to Sweden, and returned to Amsterdam, where he died. He was buried in the family grave in the in Dordrecht.R. Porter: The Crispe Family and the African Trade in the seventeenth Century, p. ?. In: Journal of African History. 9, 1, 1968, ISSN 0021-8537
