Unlike sentences such like 私は家に帰る vs. 我家へ帰らん, there is not much difference between modern and classical Japanese titles of those kind of journals. In fact, 旅行記 (lit. record of (my) journey) is quite commonly used even now. If you want to add "classical" nuance to the title, 旅行記 is not a good choice. Is Shimazu's journal only about his serving in the army there, or his entire journey after leaving Japan?
Shimazu began this journal while aboard the
HMS Syren during the British army's voyage across the ocean to North America. The contents of the journal are his day-to-day observations of serving as a military physician for the Braddock expedition. To answer your question, the journal would include entries from late 1754 until his death, which I can't divulge without giving away too much. I would appreciate your advice on whether a "classical" title would apply in this case. Also, I am including a bit more information on Shimazu's past below from the novel, how he left Japan and arrived in Europe during a time in which Japan had chosen isolation from the western world. Thank you again for your suggestions and comments!
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Born and raised in
Satsuma of the
samurai class, Shimazu displayed physical attributes at an early age that portended a warrior. Shimazu's prodigious skills with the daishō—the matched pair of traditionally made Japanese swords worn by Samurai—impressed the
daimyo, but the youth's self-discipline and wisdom secured unreserved favor with his feudal lord. With Japan flourishing in peace and the samurai having been reduced to bureaucrats, the
daimyo instructed sixteen-year-old Shimazu to instead learn the ways of medicine. The
daimyo, acutely aware of the youth's vast intelligence and looking to reduce the number of soldiers, arranged for Shimazu to begin training as a doctor.
Shimazu embraced the opportunity, traveled to
Kyoto for his education and became a notable student of medicine. He also impressed many doctors with his hand-drawn illustrations of the human anatomy. The physicians in Kyoto admired Shimazu's artistic talent with the lead pencils and ink quills, something that enabled him to sketch accurate medical diagrams. He ascended into a prominent role as a doctor in the Imperial House shortly after his twenty-second birthday in 1734. By this time Shimazu stood five-foot-eleven (extremely tall for a Japanese man) and his powerful build prompted many to call him the
oushi—the bull. But his vocation was that of a healer, not a warrior.
Having barely escaped death for violating a royal mandate in Kyoto, Shimazu and his future bride, Tsunako, fled Japan in 1738. They traveled by ship to India, where he found employment in the Dutch East India Company. He later served as a field doctor and soldier at the beginning of the Travancore-Dutch War in southern India.
Shimazu and Tsunako eventually journeyed to Great Britain, where they produced a daughter, Yoshino, in 1740. Tsunako died in 1744 from complications of dysentery, leaving Shimazu to raise Yoshino on his own in London. Though not a naturalized citizen of Great Britain, Shimazu joined the British army in 1749. His background in medicine allowed him to be assigned as a surgeon's mate on the recommendation of Sir John Pringle, who marveled at Shimazu's unique methods for treating sick patients. Pringle later informed David Middleton, the British surgeon general, of the Japanese doctor's advanced abilities in medicine, noting Shimazu would be an ideal physician in challenging locations.
Shimazu was subsequently reassigned to serve under Sir James Napier, Braddock's chief surgeon, when the British made the voyage to North America in 1755. Napier's medical staff consisted of surgeons and mates exclusively, with no doctor of primary care and medicine listed among the personnel. Shimazu would be the
de facto physician to treat illness and normal medical concerns during the expedition. To avoid political bickering in choosing the Japanese man instead of an expensive English physician, Pringle and Middleton clandestinely enlisted Shimazu as an apothecary under the
nom de guerre of William Couch.
Once they reached North America, Napier instructed Shimazu to discard the William Couch alias and begin work as a physician. The Japanese man also shouldered the responsibility of protecting his daughter in the wilderness of the New World.