From the 1830s until 1852, she was a dominant figure of the Atlantic slave trade from Guinea, and known for her conflict with the British Royal Navy Anti-Slave Squadron.
[1] In 1816, she married an American shipowner, Paul Faber (d. 1851), who in 1809 had established himself as a slave trader in the Conakry region.
[2] Through her responsibility for the company's base, Mary Faber was also responsible for the complicated policy of alliances and balance of power with local tribes and other merchant families, as the region was dominated by slave-based free slave traders who were operating in various alliances with local tribes and sometimes involved in conflict and warfare with each other.
[2] In 1842, Mary Faber and her colleague, Bailey Gomez Lightburn, joined their armies to help their allies, the Fula, to plunder the Susu capital, Thia, when weakened by throne fighting, and installing their own candidate there, which benefited Fula, Faber, and Lightburn.
[2] Mary Faber, who perceived the treaty as a hostile act from the lower river trader in alliance with Freetown's "mulatto" and also as a way of releasing the lower river's Susa tribe from her allied Fula tribe power, which would hurt her business, closed alliance with her colleagues Lightburn and Charles Wilkinson and ravaged the Susu region by the lower river.