James Gandolfini may have been best known for his work in television and movies, but the actor was also an unsung hero for injured military veterans. 

The 51-year-old, who passed away Wednesday (June 19) from a heart attack, produced two documentaries for HBO focused on veterans' issues: "Alive Day Memories: Home From Iraq" in 2007 and "Wartorn 1861-2010" in 2010. 

In an interview, the actor revealed that he was inspired to help give a voice to veterans after traveling to Iraq in 2004 and then visiting Walter Reed Hospital in Washington, D.C. 

"It all started when we were doing “The Sopranos” and I would get letters or feedback from people saying the soldiers [in Iraq], they would go out and patrol and then they’d come back and watch 'The Sopranos',” Gandolfini told the NY Times. "Tony Sirico [who played Paulie Gualtieri], who was a Marine, and I decided to go over there. Sheila Nevins, who was the head of documentaries at HBO, found out about this and decided that it would be interesting to do this documentary. Then I was going to go back to Afghanistan and Iraq with Tony Sirico again just to walk around and say hello to guys — we don’t sing and dance. She wanted to do something about post-traumatic stress from the Civil War on, and I said sure. We talked to a lot of guys, and they were pretty open with us. Gen. Ray Odierno [then commanding general of U.S. forces in Iraq] said he would talk to me, which I was reasonably astounded by. He has a lot to do, head of everything in Iraq."

In "Alive Day," for which the Times praised Gandolfini's "dignity and reserve" as host, the actor profiles 10 injured Iraq War veterans and the challenges they face readjusting to society and family life. 

"This was an opportunity to let them speak," Gandolfini told HBO. "And they wanted to talk. I wasn't pulling anything out of anybody. I just sat there and asked questions the way anybody would. They want to get the story out. They've been through so much, and I guess they feel like no one is listening, and no one cares."

Inspired by his first effort, the actor's second film "Wartorn" went deeper into the effects of post traumatic stress disorder (PTSD) throughout American history, from 1861 to 2010. Filmmaker Jon Alpert said the reputation Gandolfini earned in military circles made access to important players that much easier. 

"There's a great respect for Jim Gandolfini and when he comes knocking, they're more than happy to open the door," said Alpert. "In terms of making the documentary, his participation was very important for shortening the amount of time it takes to get people to really reveal some of the things that under normal circumstances it will take filmmakers some time to get to start talking about."

Alpert also revealed that Gandolfini was adamant about not being a distraction on camera. "It’s hard for me even to describe how unpleasant it is for him to be on camera,” he told The Daily Beast. “He would prefer it if he were the invisible man. That’s the role he would like most instead of the roles that he’s had."

In response to his death yesterday, HBO released a statement saying: "We're all in shock and feeling immeasurable sadness at the loss of a beloved member of our family. He was a special man, a great talent, but more importantly a gentle and loving person who treated everyone — no matter their title or position — with equal respect. He touched so many of us over the years with his humor, his warmth and his humility. Our hearts go out to his wife and children during this terrible time. He will be deeply missed by all of us."

Back in 2007, Brian Williams interviewed Gandolfini and some of the veterans he profiled for "Alive Day" in a segment for "NBC Nightly News." Check it out below. 

Michael d'Estries ( @michaeldestries ) covers science, technology, art, and the beautiful, unusual corners of our incredible world.

Remembering James Gandolfini and his work with military veterans
Actor produced two documentaries for HBO focused on injured military veterans, the effects of post-traumatic stress disorder, and the emotional cost of war.