Ruy Barbosa de Oliveira (5 November 1849 – 1 March 1923) was a Brazilian polymath, diplomat, writer, jurist, and politician.
Born in Salvador, Bahia, he was a federal representative, senator, Minister of Finance and diplomat. For his distinguished participation in the 2nd Hague Conference, defending the principle of equality among nations, he earned the nickname "Eagle of the Hague". He ran unsuccessfully for the Presidency of Brazil in 1910, 1914 and in 1919.
Ruy Barbosa gave his first public speech for the abolition of slavery when he was 19. For the rest of his life he remained an uncompromising defender of civil liberties. Slavery in Brazil was finally abolished by the Lei Áurea ("Golden Law") in 1888. Part of Barbosa's legacy to history is that he authorised, as minister of finance on 14 December 1890, the destruction of most government records relating to slavery. The avowed reason for this destruction, which took several years to be enacted and was followed by his successors, was to erase the "stain" of slavery on Brazilian history. However, historians today agree that Barbosa aimed to prevent any possible indemnization of the former slave-owners for this liberation. Indeed, eleven days after the abolition of slavery, a law project was deposed at the Chamber, proposing some indemnization to the slave owners.
Barbosa's liberal ideas were influential in drafting of the first republican constitution. He was a supporter of fiat money, as opposed to a gold standard, in Brazil. During his term as finance secretary, he implemented far-reaching reforms of Brazil's financial regime, instituting a vigorously expansionist monetary policy. The result was chaos and instability: the so-called fiat experiment resulted in the bubble of encilhamento, a dismal politic-economic failure. Due to his controversial role during it, in the following administration of Floriano Peixoto, he was forced into exile until Floriano's term ended. Years later, after his return he was elected as a Senator. He headed the Brazilian delegation to the 2nd Hague Conference and was brilliant in its deliberations. As candidate of the Civilian Party in the presidential election of 1910, Barbosa waged one of the most memorable campaigns in Brazilian politics. He was not successful and lost to Marshal Hermes da Fonseca. He ran again in the elections of 1914 and 1919, both times losing to the government candidate.
During World War I, he played a key role among those who advocated the Allied cause, arguing that Brazil should be more involved in the war. Barbosa died in Petrópolis, near Rio de Janeiro, in 1923.