Cuba and Brazil followed long and indirect paths to abolition. In Cuba nationalist rebels fought for independence from Spain in the Ten Years’ War (1868–1878). Many slaves and free blacks joined the failed anticolonial struggle. Spanish authorities sought to defuse the tensions feeding that struggle by enacting the Moret Law in 1870, which granted freedom to slaves who fought on the Spanish side in the war, to the children of slaves born since 1868, and to slaves over age sixty. By 1878 Spanish forces had defeated the nationalists, but the conflict set in motion an irreversible process of abolition. In Brazil the 1871 Law of the Free Womb also granted freedom to children born to slaves, and an 1885 law granted freedom to slaves over age sixty. Slavery was finally abolished completely in Cuba in 1886 and in Brazil in 1888, making them the last regions of the Americas to end slavery.

Abolition did not come about solely through laws from the top down. Social pressure, often exerted by slaves themselves, contributed to abolition. For example, in Cuba many officers in the nationalist army, including its second-in-command, General Antonio Maceo, were free black abolitionists. In Brazil free blacks like engineer André Rebouças, journalist José do Patrocínio, and novelist Joaquim Machado de Assis were fervent abolitionists who shaped public opinion against slavery and found common cause with a republican movement that saw both slavery and monarchy as outdated.

Slave resistance, in its many forms, also intensified in the last years of the nineteenth century. Slaves ran off from plantations in growing numbers. In many cases, they settled in communities of runaway slaves, particularly in Brazil, where the vast interior offered opportunities to resettle out of the reach of former masters. In the years preceding abolition, in some regions of Brazil slave flight became so widespread that slaves might simply leave their plantation and hire themselves out to a nearby planter whose own slaves had also run away. In the end, the costs of slavery had become unsustainable.