Brittany Howard, second from left, was still in high school when Alabama Shakes first got together. The group also includes Zac Cockrell, far left, Steve Johnson, second from right, and Heath Fogg.

Five months ago, Alabama Shakes couldn’t get a gig in the state they’re named after, the state they’re from. By March, Alabama Shakes will have played sold-out shows in Brooklyn, Los Angeles and London — all without an album to their name.

On the strength of a four-song, self-released EP and word-of-mouth support, Alabama Shakes have gone from relative obscurity in their hometown of Athens, Ala., to being named one of MTV’s Artists to Watch in 2012.

“I know how it’s happened, I see all the parts and pieces,” says Brittany Howard, the Shakes’ singer. “But I didn’t expect people to receive it the way they have.”

In July, Justin Gage, founder of the popular indie-music blog Aquarium Drunkard, asked Howard if he could post the song “You Ain’t Alone.” “I didn’t understand the concept of blogs,” Howard says. “I don’t even have the Internet.”

She agreed anyway, and the next day, the powerful retro-soul song started making the rounds on other blogs. When Howard awoke, she had voicemail messages from Gage asking if he could give out her number to record labels.

In what felt like an instant, a song Howard began writing a year earlier while driving in her car would unlock a world she and her bandmates had only imagined. “I always told myself, ‘I guess I’m going to live one of those lives where I dream, raise a bunch of children and think: It would have been nice if I could have done [music], but I didn’t,’” she says.

Now, “You Ain’t Alone” is featured in a Zales commercial, and the band is almost finished recording its debut album, which will be released in April on Dave Matthews’ ATO Records.

Not bad for a group that formed while Howard, now 23, was in high school. At age 3 or 4, Howard would sing along as her great uncle’s bluegrass band jammed in his woodworking shop. She knew only two songs — “Wild Thing” and “Hound Dog” — but she gave it her all. “I was hamming it up,” she says.

Her voice eventually developed into the force it is today; name any soul singer from the ’60s or ’70s, and you can hear a bit of him or her in Howard. But the Shakes have influences no one would expect. When the album comes out, “we’re either going to lose a lot of fans who thought we were one thing, or we’re going to gain some,” Howard says.

Howard knows the momentum can’t last forever. “I understand that this is going to be a time we’re going to have to treasure because you always watch bands break free” and then fade out, she says.

For now, she’s just relishing the moment. “I haven’t been this happy since I was a little kid,” she says.

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