Feudal Japan was a time of tradition, honour and warfare, with very few outsiders ever privy to the way of the samurai, especially in the sixteenth century. However one such man, a slave from Africa, firmly grasped his place in Japanese folklore.
Yasuke was an African slave attached to the Jesuit Catholic mission from Italy and was brought to Japan on a missionary trip in 1579. He became quite famous while in the country, notably because most Japanese had not seen an African before, let alone a man over six feet tall.
Word of this strange foreigner had soon reached the ears of the infamous Daimyo (a Feudal Japanese lord) Oda Nobunaga who was very eager to meet the man everyone was talking about. Nobunaga was notably impressed by Yasuke's strength and stature, and his ability to speak Japanese (which Yasuke had learned in his early time in Japan). Nobunaga however did not believe that this outsider was in fact Black skinned, and ordered him to be stripped and washed thoroughly to expose his true skin colour. When the 'blackness' wouldn't wash away, Nobunaga gave him the name Yasuke, an honour rarely bestowed upon foreigners.
The indentured Yasuke soon found himself in the servitude of the Japanese Lord, where he enjoyed far more freedoms that he ever would have in the western world (and far more so than any other slave at that time). He enjoyed his time with Nobunaga and grew in esteem and friendship with his Lord, he was given the freedoms of dining with the Japanese and earning money, and eventually he was bestowed with a samurai rank by Nobunaga.
Yasuke's rise in rank didn't win the favour of the all of the samurai, and not before long Nobunaga was betrayed by his main general, Mitsuhide. After a fierce battle raged, Mitsuhide's forces overwhelmed Nobunaga, and Nobunaga committed seppuku (a Japanese honour ritual to disembowel one's self in defeat).
With his Lord and savior dead, Yasuke joined the forces of Nobunaga's son (Nobutada). It wasn't long before Nobutada's forces were overrun in the castle that they were defending, with Yasuke valiantly fighting to the last man.
Once the battle was done, Yasuke surrendered his katana to Mitsuhide for seppuku, but Mitsuhide didn't take (or respect) Yasuke as a real samurai, and denied him the honour. Mitsuhide instead sent the captured Yasuke back to the Italian Jesuits in Kyoto.
Soon after arriving back in Kyoto, Yasuke disappeared from sight and was not heard from again. Many suspect Yasuke spent the rest of years wandering as a Ronin (masterless samurai) in feudal Japan.