In 1926, 20-year-old American Gertrude “Trudy” Ederle, a daughter of German immigrants, was the first woman to swim the 21-mile English Channel.

Two million people celebrated her ticker tape parade in Manhattan.

Now “Young Woman and the Sea” – streaming on Disney+ Friday – brings Ederle’s story to vivid life with Daisy Ridley (Rey in “Star Wars”) as Trudy.

Norwegian director Joachim Rønning “was shocked I didn’t know Trudy’s story,” he said in a virtual press conference earlier this week. “It was such a worldwide event when it happened. It changed women’s sports forever.”

Rønning, Oscar-nominated for “Kon Tiki,” another true sea saga, noted, “This had what I look for as filmmaker: warmth, emotions, humor. And it’s scary. I’m proud to be able to tell this to my teenage daughters.”

Ridley had many physical challenges because instead of a tank in a studio, Rønning wanted her in the ocean.

“Reality is great! You feel her in that cold water, and the wind and all the things that go with it,” said producer Jerry Bruckheimer (“Top Gun: Maverick”). “All the cold water and stress she has to go through and helps her acting. She’s doing the same things Trudy is doing. That’s Joachim’s style, bring everything real on camera.”

The director agreed.  “From very early on we decided to film it as real as we could. I remember warning Daisy that that was the situation — and I couldn’t have asked for a better film partner when we were out there in the ocean, 60 degrees in the water with the currents and it’s raining.

“And my biggest fear is the propellers in all the boats around her — it’s a stressful environment. But it informs us just a little bit of how it was for Trudy.

“We weren’t out there risking our lives but I hear from people, they can feel it. This is real. At the end of the day we’ve captured something magical.”

“It felt, honestly, impossible at the beginning. We trained for three months before filming but it was all in the pool,” Ridley said. “That’s all different when you get to open water. The temperature is different. The anticipation in some ways was worse.

“In Bavaria it was so cold and because Trudy is wearing her ‘bikini,’ there was no wet suit.

“I said I wasn’t going to complain beforehand but it was an amazing element of life imitating art. Because I was swimming by myself and to the left was the safety team and my hair and makeup.

“It felt isolating but it was a momentary understanding of what Trudy did. It must have been so lonely.”

“Young Woman and the Sea” streams on Disney+ Friday.