[4] In 1855, these contacts alerted him to the fact that Townsend Harris, who had been appointed the first United States Consul-General to Japan, was looking for a personal secretary and interpreter in the only European language the Japanese were familiar with.

[6] The two were the only resident Westerners in the town, and lived in intense isolation, with the local citizens exhorted to avoid them and subject to constant police escort, which they freed themselves from only after repeated objections.

[7] The first delivery of correspondence and news from home only arrived via Hakodate after a full year had elapsed, prompting Heusken to bemoan his state as a "poor ignoramus, who hardly knows whether the world still exists".

[8] Negotiations began with the local governors of Shimoda, as Heusken worked closely and constantly with Harris, being required to translate every document exchanged and interpret at every meeting.

Harris insisted on traveling to the capital city of Edo, to present his Consular commission and deliver a letter from President Franklin Pierce to the Shogun personally.

Lord Elgin was grateful for the assistance, writing to Harris: "I have found Mr. Heusken not only well qualified as an Interpreter, but in all other matters which I have had to refer to him, both intelligent and obliging in the highest degree".

[14] This offense to the sensibilities of some anti-Western locals resulted in multiple outbreaks of violence involving Heusken, including an attempted stoning by a mob while riding with the Dutch Consul Dirk de Graeff van Polsbroek.

[20] After having dinner with Count Eulenburg on the night of January 15, 1861, Heusken was returning to his quarters at Zenpuku-ji accompanied by three mounted officers and four footmen bearing lanterns.

[1] Immediately after the funeral, most western diplomats retreated from Edo to Yokohama and brought ashore greater numbers of French and British soldiers for protection as trade dwindled.