This paper aims at showing the Brazilian Navy used to be one of the routes followed by fugitive slaves throughout the nineteenth century. Some works have already been published on free slaves that took part in the war against Paraguay. However, with regard to non-emancipated slaves ¾ those who escaped and cheated the apparatuses of both the police and conscription during the nineteenth century ¾ historiographic comments are rather scarce. The author has analyzed official communications exchanged between the court’s chief of police and the officer in charge of Navy headquarters, which have revealed flaws in enlistment caused by the need to man warships and by police interest in ridding themselves of men regarded as vagrants or beggars, as well as minors etc. On the other hand, in wartime and during political crises and revolt slaves could give variable meanings to the word freedom. During the process of independence, the Sabinada rebellion, the war against Paraguay and other times of crisis, slaves would escape, cheat draft officials, take up their posts on the front in either loyalist or separatist forces, and thereby gain liberty. That freedom, however, was not to be ensured unless they fought tooth and nail for the cause of war, all of which discloses a political meaning not so much related to the branch of the armed forces they were enrolled in as to their own personal interests.