The novel contains many realistic details based on Childers' own sailing trips along the East Frisia coast, and large parts of his logbook entries from an 1897 Baltic cruise "appear almost unedited in the book." The yacht "Dulcibella" in the novel is based upon "Vixen", the boat Childers used for his exploration. In August 1910, inspired by the work, two British amateur yachtsmen, Captain Bernard Trench RM and Lieutenant Vivian Brandon RN, undertook a sailing holiday along the same section of the Frisian coast, during which they collected information about German naval installations. The two men were sentenced to four years custody by a military court in Leipzig, but they were pardoned by the Emperor in 1913. They joined "Room 40", the intelligence and decoding section of the British Admiralty, on the outbreak of war.