Politician, Lawyer, Philosopher, University professor of metaphysics in Madrid and President of the First Spanish Republic in 1873. He was part of the Krausista movement and a believer of the Institución Libre de Enseñanza. He was a close friend of Francisco Giner de los Ríos and Julián Sanz del Río.

Salmerón was a democratic republican. He was imprisoned in El Saladero in Madrid in June 1867, for a duration five months. He probably coincided with Clavé, whose letters are from September 1867. He believed in the First International and the right of association for the working class.

In 1874, Salmerón went into exile to Paris. From there, he founded the Partido Republicano Progresista, in association with Manuel Ruiz Zorrilla. He went back to Spain in 1885, after Práxedes Mateo Sagasta’s 1881 amnesty. At the end of his life, he supported a moderated Catalanismo and was a member of Solidaritat Catalana.

Salmerón published in several newspapers, among them La Discusión y La Democracia. He founded the newspaper La Justicia.

One interesting anecdote is that he was the defense lawyer in the famous trial of the Fuencarral street murder in Madrid, in 1889.