The Highwomen -- country music's new female supergroup -- made their official debut on Monday night (April 1), during Loretta Lynn's birthday celebration concert in Nashville. Together, Brandi Carlile, Maren Morris and Amanda Shires and newly unveiled Highwomen member Natalie Hemby performed "It Wasn't God Who Made Honky-Tonk Angels."

Hemby led off the performance, taking the first couple of lines of the song, and Morris finished the first verse. The four harmonized during the song's chorus, then Shires and Carlile split the second verse.

Written as an answer to Hank Thompson's "The Wild Side of Life," "It Wasn't God Who Made Honky-Tonk Angels" was originally recorded by Kitty Wells in 1952, and became the first song by a solo female artist to hit No. 1 on the Billboard country charts. Lynn, Dolly Parton and Tammy Wynette covered the song for their 1993 album Honky-Tonk Angels; Wells makes a guest appearance on that version of the track.

Their performance at Lynn's birthday celebration was the Highwomen's first public performance. Shires first teased that the collective was in the works in an interview in early January. Photos of Carlile, Morris and Shires in the studio together surfaced in early March.

In interviews, the three have explained that they'll be joined by a rotating cast of guests, and are working with producer Dave Cobb on their music. Their name is a play on the Highwaymen, the supergroup comprised of Willie NelsonKris KristoffersonWaylon Jennings and Johnny Cash, and isn't a pot reference, but rather a nod to their goal of lifting women up.

See More From Loretta Lynn's Birthday Celebration

Lynn's Bridgestone Arena birthday concert was in celebration of her 87th birthday, which is coming up on April 14. In addition to the Highwomen, the show also featured performances from Garth BrooksAlan JacksonMiranda LambertLittle Big TownMartina McBrideKacey MusgravesDarius RuckerGeorge Strait, Jack White, Trisha Yearwood and many, many more.

Lynn has appeared in public sparingly since suffering a stroke in May of 2017, followed by a broken hip due to a fall in January of 2018. “I think people thought I wouldn’t come back from that,” Lynn admitted in October. “And they’re really shocked when I tell them, ‘Well, I’m doing good, I’m moving my arms, I’m moving all my parts, and I can still sing.’”

Lynn's newest album, Wouldn't It Be Great, dropped on Sept. 28. She'd postponed the project's release following her stroke, so that she could recover well enough to support the album.

“I don’t have nothing to prove, but I have stuff I want to do," she added back in the fall, "and my fans want me to do it too."

Loretta Lynn Through the Years