“Lee” is a sturdy, episodic and sometimes moving “what I did in the war” biography of combat photographer Lee Miller.

She was a pioneer in the field, breaking down barriers, making her mark at the time. The reason we’ve not heard much about her is that she was an American model-turned-photographer, she published her work in British Vogue, and some of her most important work wasn’t published until much later.

Kate Winslet brings her to fiesty, uncompromising life in an occasionally immersive history lesson served-up with a dash of cinematic license when the unadorned literal truth isn’t sufficient.

We meet brash Lee Miller in the pre-war South of France, hanging out with artists and models and other beautiful people who aren’t shy about shedding their tops. Her friends include Picasso (Enrique Arce), a noblewoman and journalist for French Vogue, Solange D’Ayen, played by Oscar winner Marion Cotillard, and the famous French poet Paul Éluard (Vincente Colombe).

They’re an artsy, louche crowd, but they’re how the cynical Lee meets the artist Roland Penrose (Alexander Skarsgård), the love of her life.

Lee is a great beauty who doesn’t need to be reminded that typically, “ex-models travel the world and pretend to be interesting.” She may return to London with Penrose, but she’s a photographer hellbent on making a mark behind her Rolleiflex.

Vogue editor Audrey Withers (Andrea Riseborough) eventually finds a place for her, despite the sniping of famed staff photographer and future Oscar-winning designer Cecil Beaton (Samuel Barnett). And once there, when the war they all see coming finally begins, Miller becomes an integral part of British Vogue’s determination to “do our part” by showing British women doing theirs.

Miller captures women pilots who deliver bombers from the factory to air bases, nurses and anti-aircraft crews and those who simply “keep calm and carry on” during the Blitz.

After D-Day, she becomes an accredited American correspondant, getting around Britain’s rules against allowing women to cover combat. And she works the angles to break down the barriers the U.S. military throws up in front of her as the Allies march across Europe.

Andy Samberg plays Life Magazine photojournalist David Scherman, and they become a “team” and — it is implied — something more as they document battles, the liberation of Paris and The Holocaust.

Some of the most intriguing scenes here are recreations of how they sidestepped restrictions and curried favor to gain access to Nazi suicide scenes, the head-shaving punishmen of French “horizontal collaborators,” death trains and concentration camps. Hitler’s Munich apartment became the site of of one of Miller’s most famous poses and Scherman’s most famous photographs.

Cinematographer (“Summer of Sam,” “Eternal Sunshine of the Spotless Mind”) turned documentary and TV director Ellen Kuras ensures her feature debut looks documentary-real in the combat and wartime scenes and sun-drenched and somewhat carefree in the pre-war sequences.

The film meanders a bit, especially in the later acts. It’s somewhat hampered by a three-handed script that leans on a post-war interview “interrogation” Lee endures late in life, prompting her to recall her wartime efforts and exploits, dismissing them as “just pictures” but letting us see the images that were much more than that.

But Winslet is convincingly flinty, uncompromising and American in the part, a feminist in the truest traditional sense of the word. Excellent supporting cast aside, she’s the reason to see “Lee,” a one woman argument for why what Lee Miller documented and how she documented it mattered in a movie that honors her memory, and the memories that haunted her to the end of her days.

Rating:R, graphic war crime footage, violence, alcohol abuse, smoking, nudity and profanity

Cast: Kate Winslet, Alexander Skarsgård, Andy Samberg, Andrea Riseborough and Marion Cotillard.

Credits: Directed by Ellen Kuras, scripted by Liza Hannah, Marion Hume and John Collee, based on a biography by Anthony Penrose. A Sky production, a Roadside Attractions/Vertical release.

Running time: 1:56