This article follows the career of the Brazilian physician Henrique da Rocha Lima, one of the first to join the group of young researchers working at the Instituto Soroterápico de Manguinhos (Instituto Oswaldo Cruz). It describes his first voyage to Germany where he specialized in microbiology and pathological anatomy, training that shaped his subsequent professional identity. The tensions and dilemmas experienced by Rocha Lima provide an insight into what it meant to dedicate oneself to a scientific career in Brazil at the start of the twentieth century. They also reveal the importance of the relations with the German-speaking world for the experimental medicine that became established under the leadership of Oswaldo Cruz.