Japanese slave women were occasionally even sold as concubines to Indian and African crewmembers, along with their European counterparts serving on Portuguese ships trading in Japan, mentioned by Luis Cerqueira, a Portuguese Jesuit, in a 1598 document. Japanese slaves were brought by the Portuguese to Macau, where some of them not only ended up being enslaved to the Portuguese, but as slaves to other slaves, with the Portuguese owning Malay and African slaves, who in turn owned Japanese slaves of their own.