Steven Spielberg wasn't even sure anyone would want to watch Saving Private Ryan.

He'd already proved that audiences would pack a theater for the toughest of subject matter with 1993's Schindler's List, which won seven Oscars, including Best Picture and his first Best Director statue. But the Holocaust drama was a deeply personal film that he felt his entire career making relentlessly pleasing blockbusters (including Jurassic Park, released the same year) was leading up to.

And maybe, he thought, this new film—with its literally gut-wrenching depiction of the Allies landing at Normandy beach on June 6, 1944—was too much.

Five more Oscars and $483 million later...

"Certain associates and other people in my life were saying that I made it too tough," Spielberg recalled to the Los Angeles Times in 2018. "I feared that almost nobody would see it because the word of mouth would spread quickly after the first 25 minutes."

That opening D-Day sequence is indeed one of the harder watches in cinema history, but everyone should see it at least once, a reminder of how ugly combat is and how even a clear-eyed purpose can't make it glorious.

After that, how you choose to mine the otherwise very watchable, albeit heartbreaking, treasure that is Saving Private Ryan is up to you.

In honor of the film's 25th anniversary, don't just sit there and watch someone else read these secrets about the World War II classic:

"I've seen friendships that ended because of a bad moviemaking experience, and I was really reluctant to do it because of that," Tom Hanks told Deseret News in 1998. "Sometimes I'm just astounded that I know this great guy and that I'm friends with him. So it hasn't been worth it to risk our friendship until now."

His friendship with Steven Spielberg that is.

"Yes, we're still speaking," Hanks said after their bond survived their first of now five actor-director collaborations. "There were a couple of tense moments when we might have questioned each other's judgment, but we got through it."

Saving Private Ryan took 59 days to make, the first 25 of which were spent filming the 23-minute, $12 million opening sequence—shot at Curracloe, on the southeastern coast of Ireland—depicting Allied forces storming the beach at Normandy.

Roughly 400 crew members, 1,000 Irish Army reservists and dozens of extras—including amputees playing soldiers who had limbs blown off on D-Day—came together to make it happen.

"We had to build a lot of service roads from scratch just to take in the trucks with all the hardware, and we had to construct the battlements, bunkers and attack vantage points. It was the biggest logistical plan of the entire movie," associate producer Mark Huffam told the Irish Independent in 2006. "We wired off about a kilometer of beach in total for the scene. Steven  just has a way of making these things work. He'll always find a way."

Spielberg also shot underwater—using a camera on a crane set on a 40-foot flatbed trailer backed into the water—to give an idea of just how many soldiers were cut down before they even made it ashore.

"The first day of shooting the D-Day sequences, I was in the back of the landing craft, and that ramp went down and I saw the first 1-2-3-4 rows of guys just getting blown to bits," Hanks told Roger Ebert in 1998. "In my head, of course, I knew it was special effects, but I still wasn't prepared for how tactile it was. The air literally went pink and the noise was deafening and there's bits and pieces of stuff falling all on top of you and it was horrifying."

Oscar-nominated screenwriter Robert Rodat came up with the premise after reading historian Stephen Ambrose's D-Day: June 6, 1944: The Climactic Battle of World War II and then walking past a New Hampshire monument to men killed in battle—where he noticed just how many sets of brothers were killed in action over the course of one war.

The Ryans were inspired by the Niland family, who lost two sons in WWII before their third, Fritz, was reluctantly sent home, courtesy of the U.S. War Department. (The official Sole Survivor Policy wasn't implemented until 1948.)

Spielberg was reluctant to let 2nd Ranger Battalion Captain John H. Miller, English teacher-turned-leader of men in battle, kill anyone. (And we're talkin' Nazis here.) 

"'I don't think I want to see John Miller fire his gun and kill Germans,'" Hanks, talking to the New York Times, recalled the director saying. "I told him: 'I'm sorry, Steven. You're not going to get me all the way over here and turn me into some other guy just because you don't want Tom Hanks to kill soldiers.'"

Spielberg wanted a not particularly famous actor to play Pvt. James Ryan, who doesn't know he's the only one of four brothers still alive and is about to be given a one-way ticket home—and then is kind of a jerk about it once Miller's squad finds him.

Robin Williams introduced the director to up-and-comer Matt Damon on the set of a little indie called Good Will Hunting. Spielberg had seen Damon in Courage Under Fire, the filmmaker told Ebert, and liked his "American every-boy look."

By the time Saving Private Ryan came out, the every-boy was Oscar-winning toast of the town Matt Damon.

The actors did six days of boot camp—courtesy of Marine Corps Capt. Dale Dye, who put Hanks through his paces for Forrest Gump—to teach them how to hold and fire weapons and otherwise believably play battle-tested soldiers.

"I went in knowing that it would be a full-blown experience and Dye was not going to compromise for a moment," Hanks told Ebert. "The other guys, I think, were anticipating camping in the woods and maybe learning a couple of things and sitting around the campfire."

Meanwhile, Dye trained Damon separately, so he wouldn't form a bond with the actors playing soldiers who spend a lot of time ticked off that they have to further risk their lives to find this Ryan guy.

Adam Goldberg excelled in the bayonet-handling portion of boot camp. Pvt. Stanley "Fish" Melling was supposed to get shot toward the end of the film, but considering his new skill set he was given a fight scene and an unforgettable demise at the end of a German bayonet.

And, it could've been worse!

"There was a lot more of what you saw in the rough cut," Goldberg told the LA Times. "It was so graphic that Steven's projectionist...told him he can't leave the scene in the movie. It's too painful to watch."

The scene in which Jeremy Davies' Cpl. Timothy Upham doesn't come to Melling's aid was conceived the day of filming.

And there's a reason the oft-infuriating soldier froze instead of fired when he was really needed.

Halfway through the shoot, Davies recalled to the LA Times, Spielberg told him he'd realized "Upham represented the audience more than any other character, given that, of course, most of us will never experience war, and Upham was only trained to serve as an interpreter in noncombat situations."

Though we all like to think we'd do better, don't we?

When Barry Pepper was cast in his breakout role of ace sniper Pvt. Daniel Jackson, he was rooming in L.A.'s San Fernando Valley with his friend and fellow Canadian Ryan Reynolds.

Tom Sizemore, who plays Miller's second-in-command, Sgt. Horvath, was supposed to be in the other WWII movie that came out that year, The Thin Red Line, but he couldn't turn down a chance to work with Spielberg.

"He came right out and said, 'Do you want to go to Australia with Terry Malick or do you want to come to Great Britain and Ireland with me and Tom Hanks?'" Sizemore told the LA Times in 2018. "And I told him I wanted to go to Great Britain and Ireland."

It might not seem important that Spielberg had seen a short called "Multi-Facial" and an indie film called Strays, but it is because he wanted to meet the director of both—Vin Diesel—to talk about a role in Saving Private Ryan.

"He asked me to meet him on the set of Amistad," Diesel, who was working as a telemarketer to make ends meet at the time, told the LA Times. "And I remember thinking, 'How should I look?' He's writing a role for me based on my being a director, so what do I do here? And what was I going to say to him? I promised myself I wouldn't say something he's probably heard a thousand times, like, 'I'm a big fan of your work.'

"And, lo and behold, I get in front of him and he says, 'I'm a fan of your work,' and I say, 'I'm such a fan of your work.'"

"The very last scene we shot is the interior of the church—I think it was our only interior scene in the whole movie," Ed Burns, who played rifleman Pvt. 1st Class Reiben, told the LA Times. "At lunchtime, Tom takes the group of of us back behind the church; he's got a bottle of Jack Daniels and a bunch of shot glasses. He pours us a shot and says, 'Guys, I want to make a little toast about how great an experience it's been working with all of you.'"