The French revolutionary Louis Auguste Blanqui (1805-1881) was an unrelenting enemy of every French regime of the 19th century. The most heroic figure in the French socialist movement, he spent most of his life in prison.

Louis Blanqui was born in Puget-Théniers, near Nice, on Feb. 1, 1805. While studying and working as a journalist in Paris, in 1824 he became involved with the secret society of the Carbonari. This was the first step in a lifetime attachment to the use of conspiratorial methods to achieve political and social change. In 1827 he escaped arrest after his first battle with the police. Blanqui took part in the street fighting of July 1830 and was decorated by the July Monarchy of Louis Philippe for his part in its birth.

Blanqui soon parted company with Louis Philippe's bourgeois monarchy and joined the extreme republican opposition. He was arrested in both 1831 and 1832 for plotting...