It is a commonplace to see the German philosopher and economist Karl Marx as a towering figure in the 20th century. Banners with his benign, elderly, bearded face – rather like Renaissance pictures of God – fluttered all across communist Europe and Asia for decades. Something called Marxism flourished in one insurgency after another across the developing world. To those who loathed what they thought Marx represented, he was less of a god, more of a Mephistopheles.

What both these excellent new biographies aim to do is to make Marx a figure of the 19th century. He was not a towering figure then. He became one later only because his thought was boiled down by sections of the European Left into simple mantras about the necessity for