Early modern culture was multilingual, and so were many of the works produced across Europe and beyond its borders. The contributors to this volume draw new interrelations between different humanistic traditions and multilingual and translational writing practices using a wide range of primary sources—documents produced in Norwich, scientific treatises by Galileo and Stevin, travel accounts and dictionaries by James Howell, translations an retranslations of Antoine de Nervèze’s moral letters, Aljamiado documents and short comic plays in Spain, Jesuit pedagogical theater in New France, grammars, dictionaries and historiographical accounts in missionary contexts, and a mining law code in South Central Europe—that highlight the significance of polyglossia in early modern cultural production and transmission. Covering a wide range of languages, including Latin, Nahuatl and Turkish, their analysis invites comparison with today’s polyglot practices in a globalized world, as we also adapt to new technologies and ever-changing realities.