London’s reputation as a base for international radicalism can be traced back to the 16th century when religious radicals sought refuge from the Protestant reformation spreading across continental Europe, writes Roger Blitz.

But it was the mid-19th century when London became a safe haven for radical political activists. The collapse of European revolutions in 1848 prompted hundreds of radicals from the Continent to find the freedom of expression and association in London that was being curtailed in their homelands. Stephen Inwood, author of A History of London, said British ambivalence to radical exiles was undimmed even by an outbreak of attempted and actual political assassinations, including those of Tsar Alexander II of Russia and James Garfield, the US president, both in 1881.