The Danish-Norwegian author and Enlightenment thinker Ludvig Holberg (1684-1754) is a man of many faces. Besides having written various genres, both fictional and non-fictional, in Danish, Latin and French, Holberg is known for putting on different masks throughout his career by means of pseudonyms, fictive characters, and intertextual play. In scholarship, Holberg’s protean nature has grown into an opposition between the modern writer who left his mark on Danish language and literature until this day, and the neoclassicist who wrote a partly Latin oeuvre full of references to the Classical tradition. Due to this opposition, Holberg and his writings fit uneasily within categorisations as Neo-Latin or Danish literature. This dissertation aims to take the first steps at bridging the two scholarly traditions by studying Holberg’s anonymously published novel Nicolai Klimii iter subterraneum (1741-1745), henceforth Niels Klim. This piece of imaginary travel literature serves as a perfect case study to test the hypothesis that Holberg’s shape-shifting itself can bridge the two dominant scholarly perceptions of his authorship. Niels Klim was written in Latin, after Holberg’s successes as a Danish playwright, and in a period in which vernacular languages already dominated the production of fictional literature. Few works of Holberg have puzzled scholarship as Niels Klim has, and this mainly for three reasons: firstly, it was published in Latin, but quickly became a best-seller all over Europe due to the almost instant production of translations in multiple languages. Second, Holberg’s text has been categorised amongst others Menippean satire and an imaginary voyage, but as the first, Niels Klim is extremely late in European literary history, and as the second, it is unique in the way it plays with the Classical tradition. Thirdly, compared to one of its most commonly acknowledged examples, Jonathan Swift’s Gulliver’s Travels, Holberg’s text is more fantastical and more moralistic, making it more extreme in the two ends of the neoclassical spectrum of pleasure and instruction. The scholarly focus on Holberg’s moral project as an Enlightenment figure has led to an underappreciation of the fantasy in Niels Klim. Instead of looking at what Niels Klim is and choose a camp in the previously outlined debates, I pay attention to how these features made Niels Klim function in the literary field of the early eighteenth century. In 6 chapters, I place Niels Klim in a network of fictional travel literature of the early eighteenth century in multiple languages and hypothesise that Niels Klim’s unique place within European literature of this period can be captured by its ‘mobile’ quality. Firstly, the very thing that makes Niels Klim stand out compared to other contemporary travel literature, namely the choice for Latin, is constantly thematised, complicated, problematised, questioned, supported, and undermined. It is aware that it will be received in a multilingual environment through multiple translations, and plays with this knowledge. Unlike many other imaginary voyages, Niels Klim is thus not only a text about travel, but also a text that was designed to travel across linguistic and cultural borders. Secondly, Niels Klim thematises and problematises its own status as fiction, which makes any generic attribution difficult to maintain. Niels Klim thus also travels across generic boundaries. Finally, Niels Klim trains the reader to contrast different beliefs, interpretations and morals, and presents this method as its main aim. Niels Klim is thus meant to travel in the minds of the readers and train them as critical citizens. Because of these three characteristics, the reader of Niels Klim can never stand still while reading. It is a text that easily jumps from the level of narration to the level of the book, anticipated its own reception and again changes its reception in subsequent editions. Niels Klim is thus a very self-conscious text; it is aware of the unique position it holds and does not refrain from showing it. The three parts of the dissertation are linked to each of the elements of Niels Klim’s mobility. Part I revisits the choice of language with a functionalistic approach. In chapter 1, I discuss how Holberg thematises and problematises multilingualism inside the plot and narrative structure of Niels Klim. This close reading will lead in chapter 2 to a re-evaluation of the question of language, guided by Rebecca Walkowitz’s theory on born-translated literature. Both chapters will highlight on different levels that Niels Klim anticipates its own reception in a multilingual environment, amongst others through translation, and is therefore ‘designed to travel’. Part II focuses on the problematic link between Niels Klim and tradition. In chapter 3, the plot will be analysed as a constant negotiation of the concept of authority. Klim’s travels through the underground world thematise and problematise what Europe considers to be authoritative voices in the literary process, and plays with the narrative techniques that were commonly used to claim authority. This discussion will be brought to the level of the book in chapter 4, where I will revisit the generic authority of Niels Klim as a text. Which textual signals or contextual parameters led historical readers and modern scholars to certain generic attributions? Instead of choosing a genre, I will analyse the process of attribution and will propose this process as Niels Klim’s generic aim: it was designed to constantly question its own status as a fictional text. With this feature, Niels Klim stands in a transgeneric tradition of metafictional texts in the seventeenth and early eighteenth century, rather than in a linear tradition of a specific genre. In part III, finally, I will consider Niels Klim as a text that provides some kind of truth. Apart from being a gifted narrator, Holberg was also an educator who brought Enlightenment thinking to Denmark. Holberg does not simply provide knowledge to his readers, but trains them in reading critically. In chapter 5, this will be demonstrated by an analysis of Holberg’s play with the terms of historia and fabula. The two terms drive Niels Klim’s plot from start to finish but traditionally raise almost contradictory expectations. This evokes a reflective reading method Holberg aims at and which brings readers one step closer to moral insights. In chapter 6, this reading method will be demonstrated on the level of the book through an analysis of Holberg’s own playful but critical commentary of Niels Klim in his Third Autobiographical Letter. I show that Niels Klim was supposed to travel in the mind of the reader. Once readers stand still, according to Holberg’s moral project, they lapse into prejudices and sectarian beliefs. In conclusion, the present study offers a functionalistic re-evaluation of the European character of Holberg’s writings, and, more broadly, a first step for doing the same for the study of European literature in the early-eighteenth century.