For years, Aaron Lewis was best known as the lead singer of the rock band Staind, a Massachusetts-based act that released seven studio albums and charted more than a dozen Top 10 songs. But even while selling millions of albums as the successful group's frontman, Lewis was harboring an inner desire to return to his roots -- his country roots.

After announcing that Staind was taking a hiatus, Lewis released his debut solo country album, The Road, in 2012, on Blaster Records. The 10-track project included the Top 40 hit "Endless Summer" and was considered an innovative and diverse record, if not a huge commercial success. Lewis returned to the studio to craft more country tunes and, on Friday (Sept. 16), released his sophomore project, Sinner. The new disc, which is available for purchase on Amazon and iTunes, includes collaborations with artists such as Willie Nelson, Alison Krauss and Vince Gill, and is being released on Dot Records, an imprint of Big Machine Label Group.

Lewis recently sat down with The Boot to discuss Sinner, his connection to country music and whether or not he will ever return to the rock scene.

What is your draw to country music?

It’s what I grew up on; it’s the first music that I ever heard. As I’ve gotten older, it’s crept back into my life a lot more.

As a kid and a teenager, I ran away from it, because that’s what was being played for me as a kid, and that’s how I ended up going down the road that led me to being in a rock band for all these years. That got taxing after a while, singing about the things that I was singing about night in and night out and re-living where those songs came from every night in order to sing them correctly. I needed to give myself a new outlet and reinvent what I was doing a little bit, and do it in a matter that couldn’t have been compared to my previous project. The only thing that I could do and the only way that I could change it up and stay true to myself and true to my roots was country music.

All of the 11 songs on Sinner have a bit of an outlaw feel to them. Was that intentional?

It’s what stuck. That’s what my grandfather was listening to, was 1974 to 1980, when I spent more time at my grandparents' house than I did at my own house. That’s what I heard an awful lot of, and that’s just kind of what stuck.

Who were some of your early influences in country music?

I guess Conway Twitty was a big one. At four years old, I would go up and yank on the pant leg of a stranger and go, "You want me to sing a song for you?" and it was "Rhinestone Cowboy," so obviously I was exposed to some Glen Campbell.

If it was on the 8-track in my grandfather’s car, it was going to be outlaw country, for sure. And if it was on the radio, it was a mix of all of the country that was out during that time frame, but that was the soundtrack of my childhood.

Did you ever imagine, when you were having success with Staind, that you would be releasing your sophomore country album?

If you would have had this conversation with me 10 years ago, I’d have told you you were crazy.

I think my grandfather would be pretty proud. He was the one who exposed me to all of that music; he was the country music lover. My dad, just like I did, rebelled against that country music, too. He listened to R&B, and not country music. I think the closest I ever heard of country music, and it’s really not country music, would be, like, Gordon Lightfoot; he liked Gordon Lightfoot and Kenny Rankin, Al Jarreau, and then all the R&B stuff and Motown stuff. That was always his thing. And so he rebelled against the country music thing just like I did, because that’s what he was exposed to as a kid, except it was in the ‘50s and not the ‘70s.

Willie Nelson, Vince Gill, Alison Krauss and Dan Tyminski all appear on Sinner. Why was it important to you to have each of them sing on the record?

Well, I picked Willie because who wouldn’t pick Willie, and who wouldn’t just be ecstatic about the honor of having him on a track with you? But I feel the same way about Vince Gill, and I feel the same way about Alison Krauss, and the same way with Dan Tyminski.

I just feel really blessed that those people liked what they heard enough to want to put their voice on it. Alison came into the studio to sing on one song, and she’s on half the record. That’s pretty amazing. It’s very humbling for somebody like that to feel so strongly about what you’re doing that they wanted to be even more a part of it than what they were already committed to.

For someone who has had a successful career as a rock artist, you have a lot of respect for the country music genre.

I’ve always been confused by the blending of genres and the watering down of genres. And it’s been happening a lot with radio formats, since I started doing this.

The rock format, as an example, has almost dwindled away to nothing, and it’s now this "Jack FM" kind of a format, where instead of allowing new rock bands the space and the ability to get on the radio and get played and get heard, all of the time is being taken up by songs that were, 15, 20 years ago, that were a No. 1 hit back then. It’s not leaving any room for new bands to break out in it, because all the time is taken up by those tried-and-true No. 1 songs from yesterday and today. It’s hard to compete in a genre that’s designed that way.

Do you ever see yourself returning to rock music?

I have work to do first. I feel like it is very important for me to prove my loyalty to the [country] genre before I can start thinking about bouncing back and forth and creating the confusion that would be created by doing that. “Is he rock? Is he country?” I don’t feel like I’ve established myself enough and proven myself loyalty-wise enough to the genre to be able to do that yet.

Do I think that there would be the ability to do that somewhere down the road, without having enough of a handful of people say, "See, I told you he wasn’t committed to the genre"? Yeah, I’d like to be able to do it down the road, but not until I’ve established myself to where comments like what I just said aren’t being made.

Aaron Lewis + More Surprising Country Crossovers