The strange life story of the forgotten 19th-century revolutionary Emmanuel Barthélemy is well worth the telling, and Marc Mulholland tells it well, though the title of his new book is misleading, suggesting a lurid thriller rather than a serious biography. Barthélemy was once famous, featuring in Victor Hugo’s Les Misérables under his real name. He acted as a barricade commander in Paris during the June Days, which marked the end of the 1848 revolution in France. He was something of an enigma: unwavering in his commitment to revolutionary action throughout his life, he was prepared to kill and die for the cause, but actually ended his life on the public gallows outside Newgate Prison for a murder that seems to have had nothing to do with politics.

I was surprised to learn from Mulholland that throughout the 19th century there was no way of preventing foreigners from entering Britain and staying here for as long as they wished. This open-door policy in fact began in 1820 (after the defeat of Napoleon), but it seems remarkable