Remembered for founding both the Spanish General Workers' Union and the Spanish Socialist Workers' Party, this late 19th and early 20th-century politician and political activist served in both the Madrid City Council and the Spanish Congress of Deputies.
In the early years of his career as a political activist, he worked in the printing industry. He eventually became the president of the Association of Art Printers.
His thousands of published political articles include the 1870 piece "The War" and the 1925 piece "The Working Class Will Win."
He grew up in Galicia and Madrid, Spain, in a family of modest means; during his childhood years, he lost his brother to tuberculosis. In 1921, he married Amparo Melia.
He and his contemporary, Argentine activist Juan Justo, were instrumental in the establishment of Socialist political parties in their respective countries.