This study is a reconstruction of the life and work of the Scottish mathematician and physician Duncan Liddel (Aberdeen, 1561–1613). It deals with Liddel’s curriculum studiorum and academic career in northern protestant Germany (at the universities of Frankfurt/Oder, Rostock and Helmstedt); his participation in the debates of important intellectual circles such as that of Dudith-Sbardellati and Crato von Crafftheim in Wrocław and Tycho’s “astronomical Academy” on Hven, in Denmark; and Liddel’s eventual return to Aberdeen, where he funded a chair of mathematics and a scholarship for several students at the Marischal College and endowed the university with his scientific and humanistic library. This bio-bibliographical study, based on archival and library investigations, offers an insight into the institutions and networks that permitted a wide European circulation of scholars and ideas, as well as transfer processes of knowledge and scientific practices, during the Renaissance.