The so-called "blood tribute" (Portuguese: tributo de sangue) was how forced recruitment into the Brazilian Armed Forces was known until the introduction of mandatory military service based on the Sortition Law in 1916. An older law had already established conscription by sortition in 1874, but popular resistance from the "list rippers" prevented its implementation, and forced recruitment continued to exist in practice. In this model, incorporated contingents were small. Soldiers were professionals, sometimes serving for up to 20 years, and were not sent into reserve at the end of their service. Not all soldiers and sailors were forced into service, as there were volunteers. The state had a low degree of bureaucratization and grasp over the population, leaving the administration of recruitment to the influence of local elites. The Imperial Brazilian Army had little control over the process. Impressment of recruits was carried out by police and military detachments.
With origins in Europe, Brazilian forced recruitment had existed since the colonial period. Recruitment was violent, called "human hunting", and military service took place under harsh conditions and was considered a punishment. The free poor did their best to escape recruiters, and recruitment of workers could damage the economy. Central authorities, wishing to fill the ranks without harming the economy, lived in a precarious balance with administrative agents, who needed to fulfill the task without interfering in patronage networks, and the free population. Recruitment ran up against a large number of exemptions defined by law, such as for national guardsmen, and a network of patronage protection which kept out of reach workers protected by local elites. For patrons, choosing who would be protected was a powerful instrument of control. Recruitment fell on those who could not find protection, considered the unproductive portion of the population. Popular morality had an ideal of what fair recruitment was and who was deserving or undeserving of impressment.
Forced recruitment was not enough to fill even the small number of Army troops in peacetime. In 1874, the Minister of War estimated that it was necessary to arrest 20,000 individuals to obtain 2,000 recruits. The great demand for troops in the Paraguayan War (1864–1870) overloaded the system and created tension in its social relations. The inefficiency of mobilization was one of the reasons why the war took so long. Both military officers and reformist parliamentarians wanted to reform recruitment throughout the 19th century, seeking to civilize the "human hunt" and modernize the Armed Forces. The inspiration was European armies, whether built by compulsory military service or by volunteering. The 1874 reform attempt failed because it threatened the society's mode of coexistence with impressment, and even the first military lottery in 1916 came eight years after the new law was passed in 1908.