In May 1677, the scholars and students of Uppsala University witnessed an animated debate regarding what language should be used at their seat of learning. Was it to be Latin, the lingua franca of scholars and scientists throughout the Western world, or Swedish, the students’ mother tongue? The debate erupted after the professor of medicine Olof Rudbeck had published an invitation — in Swedish — to attend the dissection of a human body in his Theatrum anatomicum. Furthermore, the programma was formulated in a way that was perceived by some to be frivolous. The first scholar to openly criticise Rudbeck’s choice of language and blunt expressions was the renowned philologist Johannes Schefferus. In his denunciation of Rudbeck’s linguistic preferences, Schefferus emphasised the role that Latin played in the preservation of the university’s prestige. This article studies the Uppsala conflict against a background of the early modern university’s traditions and its almost exclusively Latinate milieu. The article also shows how the disagreement between Rudbeck and Schefferus in other scholarly fields contributed to their quarrel. In addition, the present contribution explores the combatants’ choices of medium, and how their disagreement fit into the context of the so-called humanist Streitkultur, a culture in which figures such as Rudbeck and Schefferus were highly skilled at a range of techniques that could be employed to belittle their adversary’s academic achievements.