She’s played countless royal and political figures, but for Dame Helen Mirren, long viewed as the quintessential British actor, playing Russian empress Catherine the Great was deeply personal.

“It was revisiting part of my life that was repressed for a long time. My father was born in Russia and so I’m half-Russian. My grandfather had been in the Tsar’s army, so we were White Russians and my father very much wanted to assimilate. So he changed our family name from Mironiv to Mirren,” she explains. “He had to accept that, that world was gone and we just had to assimilate and be British.” She reminisces about the first time she visited her ancestral home. “It was in the late 1960s and Russia was very deep into heavy Bolshevik communism. To find myself standing on the terrain that had given birth to my grandfather was a very emotional moment for me.” She pauses, composing herself for a moment. “It’s a complex relationship I have with Russia, as it was with Catherine the Great, who wasn’t Russian at all, but in fact, she was a German princess!” she laughs.

This four-part series features her legendary love affairs, including the most notable, with Count Grigory Orlov (Richard Roxburgh), and another relationship with Grigory Potemkin (Jason Clarke). Seriously ahead of her time, Catherine was also quite the advocate for women’s issues, and remains the longest-running female Russian leader, ruling from 1762-96. She came to power through her marriage to the Tsar of Russia, Peter III, her second cousin. A coup, partly organised by her lover, Count Orlov, placed her in the position of empress. “Catherine was historically maligned starting with her son with whom she so obviously had a very difficult relationship,” Mirren explains, “and he maligned her after her death. I think that calumny has stuck with her throughout history. It’s the way powerful, successful women are punished very often — for being just that, powerful and successful.

“As for her sexuality,” Mirren pauses and rolls her eyes. “The intimation that she was some sort of debauched, mad sexual creature absolutely wasn’t true. She was a serial monogamist, as so many of us are.” Her gaze is direct, and she offers, after a beat, “Me included.” Now 74, she has been married to director Taylor Hackford, since 1997. And while many women, regardless of age, find sex scenes particularly daunting, this has famously never been the case for Mirren. “It was lovely. I enjoyed every minute!” she laughs. “I think Catherine loved sex, she loved men, and she loved having a sexual relationship. She loved to have a guy around but knew it was dangerous territory because if she was to marry, she would relinquish power.

‘I think Catherine loved sex, she loved men…’ But she was always very nice to them. She gave them palaces, she even made one of them King of Poland when she wanted to get rid of him.” She laughs. Having played many queens and women in power, how would Mirren herself handle absolute power? “I would give it away. I wouldn’t want it,” she shakes her head. “It must be the most incredibly dangerous thing. And of course, no one really has it.”