'I’ve told everyone that it’s a comedy – but will anyone laugh?' Jonathan Dove on his new Marx opera

Marx is having a terrible day. He is supposed to be finishing volume two of Capital but he’s distracted by his lust for the maid, workmen are taking away the furniture, his daughter thinks she’s caught a spy.... and what will his wife say when she discovers he’s taken her silver to the pawnbroker?  Where is Engels when Marx needs him most?

The answers are in Marx in London, my new opera opening in Theater Bonn on 9 December. If the plot sounds a bit like Richard Bean’s play Young Marx, that’s because at one point I asked Richard to write the libretto for my opera, and that gave him the idea for his play. For a while, we wondered if I might wait for him to finish writing it, and then turn it into an opera. But in the end, he was more interested in Marx’s early Soho years in London, while my opera takes place in 1871, when Marx had already finished volume one of Capital and was living in Kentish Town — and his illegitimate son was old enough to make an appearance in an opera.

The idea was originally offered to me by writer-director Jürgen Weber, who suggested that the colourful and sometimes farcical events in Marx’s domestic life could be presented in a single day, following the model of The Marriage of Figaro. I had been toying with the idea of writing an operatic farce for some years, but I felt it needed to have its feet on the solid ground of reality: Marx’s domestic dramas seemed ideal. (Images from rehearsals for Marx in London by Thilo Beu). The more Jürgen told me about Marx, the more fascinating he became. All the contrasts in his nature made him deeply human, a rich character to explore: a communist bankrolled by capitalism (via the Engels family business); the champion of the proletariat who craved a bourgeois lifestyle; an expert on money who somehow never seemed to have any. Even his great writing achievements weren’t his alone: he never finished Capital, despite his years of research and copious notes; after his death, his great friend Engels completed it for him, coming to his rescue yet again.

I was touched and amused to realise that this great thinker could make such a mess of his domestic life. It made it very important to get a glimpse of his invisible inner intellectual activity, as well as his visible outward behaviour to his family and friends. Opera is a wonderful medium for feelings, but not so good for communicating complex economic theory. I never wanted to hear Marx sing any of the Communist Manifesto, or Capital – and yet I wanted to get some flavour of what sets him apart, the distinctive ideas that are peculiarly his own. So we have a scene where you can hear (albeit in a dream) Marx’s vision of what might happen in a communist world, and another scene where he tells his listeners all about capital. These are operatic scenes, of course, not economics lessons, so they offer only a glimpse of this intellectual world, but their idealism is an important counterpoint to the parts of his life that Marx didn’t manage very well.

A mixture of English and German was spoken in Marx’s house, and at first I thought we might write the opera like that. But I soon realised that, with my schoolboy grasp of German, although I could imagine ways of singing the language intelligibly, I didn’t think I could be funny in German: for that, I needed to write in my own language. That meant finding an English writer to collaborate with Jürgen, and I turned to Charles Hart, who is well known for writing the lyrics for musicals, but also has experience in opera.

Looking back, I’m glad we didn’t pursue the idea of writing in two languages: it’s hard enough for an audience to understand one language, when an orchestra is involved. In opera, you don’t always catch every word, but with luck you can hear enough to work out what you missed.  However, if the words you missed might have been in a foreign language, but then again might not, the chances of understanding anything are radically diminished.

As the premiere approaches, I’m wondering what the audience is going to make of it. There are wonderful performances to enjoy: Tussi, Marx’s youngest daughter, whose excitable music and flamboyant coloratura betray her dreams of being an actress; Jenny, driven to despair by Marx’s antics; Marx and Engels, celebrating their enduring friendship in an ecstatic duet; Helene’s deep contralto when she reveals the secret of Freddy’s birth. I’ve told everyone that it’s a comedy – but will anyone laugh?  On 9 December we’ll find out.

• Marx in London opens on 9 December at Theater Bonn and runs until 14 February
• Read opera reviews on theartsdesk