Without saying it in so many words, de Hartog portrayed the sailors, who arw doing a difficult, dangerous and poorly-rewarded job, as the modern successors to the bold navigators of the Dutch Golden Age. In fact, the book's plot as such had nothing political, anti-German, or anti-Nazi, the sailor protagonists' conflict being mainly with nature and with their highly paternalistic and authoritarian and thoroughly-Dutch employers. Nevertheless, for a country undergoing the shock of invasion and occupation, the book, with its outspoken assertion of and pride in Dutch identity l, became a bestseller in the occupied Netherlands and a focus of popular opposition to the Nazi occupation. As a result, the Gestapo took a lively interest in de Hartog himself, who had joined the non-military Dutch resistance, performed and wrote plays, and assisted in the concealment and the relocation of Jewish babies to avoid having them sent to concentration camps. His book was banned, and he was forced into hiding by assuming the identity of an elderly woman in a nursing home. Eventually, he staged a difficult and adventure-filled escape to England. His book became the best selling novel of the war years in the Netherlands. In London, he became deeply involved in the community of the exiled Dutch sailors. The exiles worked with their British allies, often by going on dangerous missions, with inadequately-armed or sometimes completely-unarmed boats. He joined the Netherlands merchant navy as a correspondent in 1943 and later served as a ship's captain for which he received the Netherlands' "Cross of Merit." The experience served as the background to several of his later books such as The Captain and . The latter was made into a movie starring Sophia Loren, Trevor Howard, and William Holden under the title The Key and also started de Hartog on the route to becoming a pacifist, which later culminated when he joined the Religious Society of Friends, also known as the Quakers. Postwar De Hartog had many hesitations about authorizing the translation of Hollands Glorie into English, and when he finally did in 1947, the English version (entitled Captain Jan) had less success as the Dutch original. However, in the wake of the war, he made the decision to remain in the United Kingdom. He also made the professional decision to write most of his later works in English, beginning with The Lost Sea (1951), which was a fictional account of