What is a “Jewish book”? Does the history of Jewish secularism necessarily follow a Christian example? Did the Jews living in early modern Europe and the Ottoman Empire understand themselves by the same terms contemporary ones do? This dissertation examines five books printed by Jewish printer Gershom (Hieronymus) Soncino (1460[?]-1534) in the late 15th and early 16th centuries, in Italy and in the Ottoman Empire, which are posited as ‘secular.’ While Gershom is mainly known in “Jewish bibliography” circles – a concept the dissertation investigates and challenges – as a printer of religious Jewish tomes, a critical microhistorical analysis of the five books, their production, material makeup and reception, reveals a ‘secularity,’ a comfort in being-in-the-world which upends the received temporality of Jewish secularization. In rejecting a retrojection of later ideas of ‘secularization,’ often Christian-inflected and ideologically-biased, onto early modern Jewish cultural production, the dissertation asks that the Jews living in Renaissance Italy and the Ottoman Empire be understood by their own lights. To correctly treat Gershom’s books a critical list of his published titles spanning five languages, was necessary: the dissertation therefore first follows the “political economy of classification” which has historically governed what material has been deemed “the Jewish book,” revealing the embedded discursive biases of this scheme and problematizing some of its techniques. It then moves to investigate the ‘world’ each of five secular books was created and consumed in. The ‘world’ of Isaac ibn Saḥula’s 𝘔𝘦𝘴𝘩𝘢𝘭 𝘩𝘢-ḳ𝘢𝘥𝘮𝘰𝘯𝘪 (1490–1491), a compendium of animal fables and the first Hebrew illustrated book in print, is treated as a series of translations between medieval Spain, northern Italy and modern Germany. What do its woodcut illustrations reveal about the representation of the human, the animal and the Jew in Renaissance Italy? The dissertation contends that they reveal a specific Renaissance visual Jewish being-in-the-world. The ‘world’ treated I a grouping of six epic titles Gershom printed in the early 16th century similarly questions ideas of Jewish visuality and national Jewish literature(s): were these chivalric and macaronic titles ‘Judaized’ as ‘foreign’ material, or did the Jews of Italy read and enjoy them all along? An economy of print reuse in these titles further reveals an economic and cultural circuit between the Marche region and Venice. The ‘world’ investigated in connection with the 1534 𝘚𝘦𝘧𝘦𝘳 𝘩𝘢-𝘮𝘪𝘴𝘱𝘢𝘳, an arithmetic primer by Elia Mizraḥi that Gershom printed in Constantinople is one of a “Trans-Adriatic circuit” of scientific dissemination, following certain problematics of intercultural and inter-religious ‘translation’ in the Renaissance. Is printing ‘Western’? Was a book printed in Hebrew in the Ottoman Empire – one of the first ever – an ‘Italian’ production? Did its different readers – Jewish and non-Jewish – understand mathematics and science as ‘secular’? The ‘world’ which a chapter on a trilingual Christian exegesis of the Talmud (𝘋𝘦 𝘢𝘳𝘤𝘢𝘯𝘪𝘴 𝘤𝘢𝘵𝘩𝘰𝘭𝘪𝘤𝘢𝘦 𝘷𝘦𝘳𝘪𝘵𝘢𝘵𝘪𝘴, 1518) investigates centers on the question of why a devout Jewish printer would publish a fiercely anti-rabbinic tract. By reading the rise of the 16th-century intellectual-religious phenomenon of Christian Hebraism against the contemporaneous invention of the world’s first Ghetto in Venice, the chapter asks whether the ‘extraction’ of Hebrew and other forms of ‘Jewish knowledge’ during this period can be read as analogous to the rising logic of race, as well as the nascent capitalistic logic of the colony prior to the colony. Questioning and following this ‘early modern extractivism,’ the chapter places 𝘥𝘦 𝘈𝘳𝘤𝘢𝘯𝘪𝘴 in its larger intellectual context, positing a secular Jewish being-in-the-world even within a religiously Christian context, rereading the modern birth of ‘Jewish studies.’ The final chapter investigates some visual aspects of the sumptuous woodcut illustration accompanying a Christian theological title, 𝘋𝘦𝘤𝘢𝘤𝘩𝘰𝘳𝘥𝘶𝘮 𝘤𝘩𝘳𝘪𝘴𝘵𝘪𝘢𝘯𝘶𝘮 (1507): were they the reason for some bibliographers’ anxieties regarding Gershom’s ‘correct’ religious affiliation? Continuing a discussion on Italian-Jewish worldliness, the chapter fleshes out Gershom’s – and other Jews of the time – adamancy to ‘be in the world’ in which they lived. Taken together, the different ‘worlds’ investigated in this dissertation feature recurring situations of polyglossic hybridity, of ‘diglossia,’ of trans-national circuits operating before the modern formulation of a nation, of a repeated crossing of borders and religious lines of demarcation, of constant translation across and between languages, as well as between the textual and the visual, between the abstract and the material. Gershom himself, the dissertation shows, exhibited a comfort and an ease with ‘being in the world.’ An intervention into both the study of religion and secularity and the history of the book, the dissertation combines insights from Italian history, Ottoman history, Jewish history, book history, art history, sociology, philosophy, and postcolonial and critical theory to counteract a “lachrymose” view of early modern Jewish culture and religion, emphasizing instead its wonderful inventiveness, malleability, intellectual brilliance and its celebration of pleasure.