John Blackthorne is the central character of the novel Shōgun by James Clavell and the NBC TV miniseries based on the book.
Born in England Blackthorne became a sailor. By the early 1600s Blackthorne was the pilot on board the Dutch ship Erasmus out of Rotterdam. As pilot he was responsible for the navigation of the ship and was second in command. The Erasmus was part of a five ship fleet sailing east on behalf of the Dutch East India Company, and was the last surviving ship in the fleet. Sailing east many of the crew fell prey to accidents and illness. The Captain was one of the casualties, leaving Blackthorne in command.
As the ship sailed out past Asia the Erasmus encountered a storm. By the time it cleared the Erasmus found herself in a Japanese harbor. The crew was taken prisoner, and the ship impounded.
Finding Blackthorne's name difficult to pronounce the Japanese samurai Kasigi Omi called him Anjin, which was the Japanese term for pilot. Blackthorne insisted the Japanese use the san honorific, after that day he became known as Anjin-san, which meant honorable pilot.
Soon after arriving Blackthorne met Vasco Rodrigues - a Portuguese ship pilot. National and religious differences meant that the two men were on different sides. However their shared occupations gave the men a foundation to build a cautious friendship upon, with Rodrigues calling Blackthorne Ingles. Blackthorne saved the life of Rodrigues when the latter was swept overboard off the galley they were on during a storm. Rodrigues later returned the favor by throwing Blackthorne off the Black Ship before its Captain Ferriera could murder him.
Blackthorne found himself caught up in the ongoing power struggles in the island and found himself the target of Jesuits who had set up shop in Japan. Wanting to know more about the English, Lord Yoshi Toranaga took him and began interviewing him, learning that Christianity and Europe itself were divided between various competing powers.
Soon Blackthorne became a trusted ally of Lord Toranaga, helping the Japanese daiymo escape certain death at the hands of his rival Lord Ishido and became a samurai himself. Blackthorne found himself in love with Toranaga's interpreter Mariko. Blackthorne also began to culturally assimilate into Japanese society. Raised to believe that baths would make one sick he was forced to take one after arriving in Japan and found himself enjoying them. The fact that he was culturally assimilating into their society was hit home when he visited his crew and was shocked to find how far he had come from the European norms. After an evening spent with them one of his first acts was to seek out a hot bath for himself.
Seeing how abusive Mariko's husband Toda Buntaro was towards her and how much he was in love with her Blackthorne approached Toranaga to request she be allowed a divorce so he could marry her. Toranaga refused the request, forbidding Blackthorne to speak of it again to him. Mariko died a short time later after an attack by Ishido and the traitorous Lord Kasigi Yabu.
Soon after Mariko's death Blackthorne discovered that the Erasmus had been destroyed by fire. The stress of the Erasmus burning proved fatal for one of Blackthorne's few surviving crewmates, Johann Vinck. Using money Mariko had left him Blackthorne began the process of building a new ship to enable him to find the Portuguese treasure ship and return home to England in triumph. What Blackthorne did not know was that Toranaga had burned the Erasmus to keep him in Japan and was intent on destroying the new ship once completed - the daimyo intended to keep him in Japan for the rest of his life.
The character of John Blackthorne was based upon the real life English sailor William Adams. Adams was one of few survivors from a Dutch East India expedition to reach Japan. Soon after arriving in Japan the rotted hulk of the ship they arrived in sank. Becoming a trusted advisor to Tokugawa Ieyasu, Adams became a samurai and hatamoto with right of direct audience to Tokugawa.