It is harder - perhaps impossible - to visualise the women who helped him through some of the greatest challenges he faced during his first weeks in office as prime minister in 1940, during the early days of the Second World War.
It is that period, as he faced pressure from within his party to pursue peace with Hitler at any cost, that is the focus of Darkest Hour, the new film by Atonement director Joe Wright.
Gary Oldman is almost unrecognisable in the part of Churchill, thanks to a face mould and foam bodysuit that took four hours to get in place, while Kristin Scott Thomas plays his stoic wife Clementine.
“These parts have been played so many times by brilliant people, like Harriet Walter in The Crown, there is a great weight to it because you’ve got to be as good as everyone else,” says Scott Thomas.
“Then there is the thing that struck me when I decided to take this on - I’m trying to portray somebody who is a national treasure.
“Clementine is less well known today than Winston but, at the time, I think she was really important. She was a proper first lady and how do you bring life into something that belongs to everybody? That is public property?
“I think that was very much her situation as well, because her husband was public property, her husband was the prime minister in a very, very tense and worrying time, a terrifying time.”
Clementine Churchill would not be the first woman in history to see her role downplayed, if not airbrushed out of history. So does this film, which makes clear their bond and her influence, redress that injustice?
“In a very small way,” she replies. “It’s not a film about Clementine. The day will come when there will be a film about Clementine and then we can talk about redressing.
“But it is very difficult to create a space for her because he is such an overwhelmingly fabulous character, in all senses of the word. Not only was he brilliant and saved us but he was also wildly entertaining and kind of eccentric.”
Be that as it may, Scott Thomas is anxious that the role Clementine played is not underestimated.
“I don’t think she does get as much credit as she should. She was a great support to him, she provoked him, she consoled him, she kicked him when he needed a boot, and they had a very stormy relationship, a very passionate relationship, which lasted for many, many years.
“I think she was absolutely part of the engine, she was at the heart of it all.”
Scott Thomas says the cast were stunned when they first saw Gary Oldman in Churchill mode.
“It was such a shock, it was an audible gasp in the room when he entered dressed as Churchill for rehearsals.
“I think it was a very clever move on his part to arrive as this character in the full get-up, the full make-up, the full costume, because suddenly we realised where we had to aim, what was at stake, how much he had invested and how dedicated he was to doing it, to getting it right, and I think that upped everybody’s game.”
It’s surprising that an actor of Oldman’s stature has never won an Oscar, even more surprising that he has only been nominated once - for Tinker Tailor Soldier Spy, losing to Jean Dujardin for The Artist in 2012.
James hopes that will all change now.
“It’s hard when you start talking about awards because it’s all such an elusive thing, where sometimes there can be no rhyme or reason for it.
“But I’ve watched Gary as an actor my whole life and been in awe of him and his abilities. There is no-one really like him.
“His ability to transform and just exist as different human beings is unparalleled.”
- Darkest Hour is in cinemas on Friday