The goal of the first International May Day celebrations was the eight-hour working day.

Eleanor Marx was her father's first biographer. All subsequent biographies of Karl Marx, and most of Engels, draw on her work as their primary sources for the family history, often without knowing it. I think if she'd been a son, she would have been referenced more.

Men want to destroy the women: you've become bigger than me, people love you more, you have a public platform, that's my space you're taking up. I can't just divorce you, I have to destroy you.

Before my book, the most common assessment of Eleanor Marx is "Yes, she's great but basically she's in the shadow of her father." Absolute bollocks. She fought him, she resisted, and she was not a kind of trocadateur of his ideas.

Many of us have had that experience of being in love with someone and then they end up being your enemy and there's a stranger in your bed.

A biography is never a biography of one person, of course, but the individual life of your protagonist will never conform. It will always bang up against history.

When you're writing, you're making decisions about compression and the shape of a life, which are very similar to how we experience our inner consciousness.