This dissertation analyzes the historical context that sets the origin of the function of ship chaplains in the world; it also tries to reflect on how this tradition became common in Brazilian ships. Upon reflecting on the nascency of the naval chaplain, the research analyzes the profile of the first naval chaplains and the challenges involving the beginnings of religious assistance aboard a vessel. Through bibliographical research, the thesis maps the presence of the naval chaplain in Brazilian historiography and Navy, encompassing the historical development on the Colony, Empire and Republic phases, and the Navy during the Portuguese Royal Armada, in the creation of the Imperial and National Armada, as well as the current phase of the Brazilian Navy. Although a majority of the research takes place in the field of History, the motivation behind the interpretation of the events is theological and pastoral, enabling a Protestant interpretation about the mission of a naval chaplain nowadays. The research reflects on the identity of the naval chaplain, his mission and pastoral challenges, the knowledges he must have and attributions of the ministry, revealing the need for the naval chaplain to correspond to the demands of the institution he represents, having the maturity to shepherd a heterogeneous and heterodox group, whilst dialoguing with ecumenism and inter-religiosity, not losing the characteristics of his confessionality. Driven by the design of fulfilling his triple constitutional mission – religious assistance, spiritual assistance, and support on moral education activities – the naval chaplain is also theologically impelled by the Christian motivation of serving people, witnessing Christ s Gospel.