Everywhere you read about that "Black Samurai" that rose from slavery to aristocracy in Japan thanks to the sense of Justice of Nobunaga, but things were quite different in reality.
The "boom" about Yasuke was introduced by a documentary of sort aired on the Japanese TV on 2013 and keen on explaining the mysteries of the world. After studying the raw materials, the conclusion of the investigation stated that Yasuke was a Makua whose real name was Yasufe.
I made the effort to check the references provided by the documentary to see how fitting was the result.
First of all, I checked the report on the subject by our first source, that François Solier who documented the Japanese missions in his "Histoire Ecclesiastique Des Isles Et Royaumes Du Japon".
Here's a translation from French provided by my kind friend Hervè:
"The day of Easter was celebrated in great devotion. After the feast, Father Alexandre went to Meaco to see Nobunaga and thank him for the favors that he continuously bestowed upon Christianity and to our fathers who were preaching in his kingdoms. However Father Alexandre had brought with him from the Indies a Mozambican valet as black as those Ethiopians from Guinea. This cafre was one of those inhabitant from Cape of Good Hope. Suddenly as soon as he arrived here, all the town inhabitants came to see him. Father Organtin brought him to Nobunanga who received him greatly and couldn't believe this skin colour was natural and believed he had been painted for fun."