On 7 June 1934, the Olympia Stadium in Earls Court was the venue for the first major battle between fascists and communists to take place in Britain. Participants are now agreed that it was a decisive battle; the argument is over why.

To Sir Oswald Mosley, it was a victory for free speech: ‘The most massive and seriously organised attempt ever made in Britain to smash a meeting by violence was heavily defeated by those conducting the meeting… after that, they (the ‘reds’) never again attacked our indoor meetings. To the left-wing journalist Frederic Mullally, the significance was quite different: ‘My anti-fascist militancy was born there in Olympia that night. It was like seeing the beast unchained coming at you with red claws and snarling teeth. That night, Mosley must have lost thousands of potential sympathisers.’