"We had never met her, but we admired her from afar," Rolling Stones guitarist Keith Richards said of Angela Davis, talking to Harper's Bazaar writer Brooke Mazurek in 2017.

Richards and Stones singer Mick Jagger wrote the band's 1972 song "Sweet Black Angel" about Davis, the Birmingham native and controversial civil rights activist.

It's a standout track on one of rock's greatest albums, The Stones' 1972 double-LP "Exile on Main St."

A mix of blues, folk and world-music, "Sweet Black Angel" is a rare snuggly tune on the otherwise piratically plastered "Exile."

"This one started as an island-lilt sort of thing when we were in Jamaica," Richards told Harper's. "After a while the words 'Sweet Black Angel' crept into it, and I realized Mick was writing about Angela Davis, the famous activist who was under arrest at the time."

In 1970, Davis, a former UCLA philosophy instructor previously terminated (under orders from California's then-governor Ronald Reagan) for being communist, now faced murder, kidnapping and criminal conspiracy charges. Guns she'd purchased were used in a deadly failed courtroom attempt to free three inmates known as the Soledad Brothers, accused of murdering a prison guard. Her spectacularly Afroed visage graced the FBI's most-wanted list. Davis went on the lam. After about two months, she was apprehended in a $30-per-day, seventh floor Howard Johnson Motor Lodge room in midtown Manhattan. U.S. President Richard Nixon called Davis a "dangerous terrorist." But she hadn't been there at that attempt to spring the Soledad Brothers, and witnesses later testified Davis purchased the firearms in question for guarding the inmates' defense headquarters, according to New York Times reporter Jennifer Schuessler. After being held in prison 16 months, Davis was finally granted bail. She stood trial in Santa Clara County, Calif., where an all-white jury acquitted her of all charges.

The Stones' ode to Davis, "Sweet Black Angel." appears on what's casually referred to as the "acoustic side" of "Exile on Main St." It's the next to last track on side two.

"Exile" is known for its swampy cinéma vérité production and decadent recording sessions, much of which took place in Richards' rented South France villa, called Nellcote. The album's most famous song is blues-pop gem "Tumbling Dice," a fixture in Stones concerts to this day.

Basic tracks for "Sweet Black Angel" were cut at Stargroves, Jagger's English country manor using the "Rolling Stones Mobile Studio," according to recording engineer Andy Johns, as told to Bill Janovitz, author of the "Exile" installment of the 33 1/3 book series.

"That was done all of them in a room in a circle at the same time, because there was this one room away from the main hall that had no furniture in it, with a wooden floor, quite high ceilings and plaster walls," Johns said in Janovitz's book. "We wanted to get the sound of the room."

On the recording, that intimate scene comes through, with a campfire-like vibe. Jagger's lyrics aren't quite "Kumbaya" though.

Got a sweet black angel / Got a pin up girl

Got a sweet black angel / Up upon my wall

Well, she ain't no singer / And she ain't no star

But she sure talk good / And she move so fast

But the gal in danger / Yeah, de gal in chains

But she keep on pushin' / Would ya take her place?

She countin' up de minutes / Countin' up de days

She's a sweet black angel, whoa / Not a sweet black slave

Ten little n — — — / Sittin' on de wall

Her brothers been a fallin' / Fallin' one by one

For a judge they murdered / And a judge they stole

Now de judge he gonna judge her / For all dat he's a worth

Well de gal in danger / De gal in chains

And she keep on pushin' / Would you do the same?

She countin' up de minutes / She countin' up de days

She's a sweet black angel

Not a gun toting teacher / Not a red lovin' school mom

Ain't someone gonna free her / Free de sweet black slave

Jagger sings in a Caribbean patois on "Sweet Black Angel." He'd employ a similar vocal tone for later Stones cuts including reggae "Cherry Oh Baby" and tribal rocker "Hey Negrita" on erratic 1976 LP "Black and Blue."

For "Sweet Black Angel," Jagger also laid-down some tasteful harmonica. The flamboyant frontman is a fine, instinctual player of this blues instrument, a point Richards frequently makes in interviews.

When not using the Rolling Stones Mobile Studio on their own projects, Jagger and company rented the unit out to other artists including Led Zeppelin and The Who. According to Philippe Margotin and Jean-Michel Guesdon's book "The Rolling Stones All the Songs: The Story Behind Every Track," recordings for "Sweet Black Angel" were also done at Nellcote, London's Olympic Studios, as well as, like many "Exile" overdubs, Hollywood, Calif.'s Sunset Sound.

The working title for "Sweet Black Angel" was "Bent Green Needles."

According to "All the Songs," Richards played his Gibson Hummingbird acoustic guitar on the song. He also sings ragged-righteous high-harmonies. A second, background acoustic strummed on "Sweet Black Angel" is either Richards or Mick Taylor, The Stones' wunderkind lead-guitarist during this era.

Jimmy Miller contributed guiro, that clicking insect-sounding percussion, on "Sweet Black Angel." He likely also played woodblock on the tune. Miller was the rhythmically savvy producer who helmed "Exile" and other albums in the mighty late '60s/early '70s Stones tetralogy: "Beggars Banquet," ''Let It Bleed" and "Sticky Fingers." He also produced notable records for bands such as Traffic, Blind Faith and Motorhead.

New Orleans musician Richard "Didymus" Washington played the sunny marimba lines that bring optimism to the "Sweet Black Angel" outro. On the original "Exile" inner sleeve Washington, introduced to The Stones by Dr. John, was credited as "Amyl Nitrate."

Some rock scribes assert The Stones rarely got political as they do on "Sweet Black Angel." But that's not totally true. When the band addressed politics in their music they just had the decency to make sure the track was still fun to listen to. For example, The Stones' politics rocked on "Street Fighting Man." On "Undercover of the Night" it was sexy.

"Exile on Main St" was released on May 1, 1972 in the U.S., according to riaa.com, via the band's Atlantic Records-distributed vanity imprint, Rolling Stones Records.

That same day in Paris, Jagger and then-wife Bianca Jagger participated in a march supporting Davis, according to timeisonourside.com, an online Stones fan database.

"Sweet Black Angel" clocks in at just under three minutes.

The band liked the song enough to use it as the B-side for their "Tumbling Dice" single, which peaked at number seven on the Billboard Hot 100.

However, The Stones have only performed "Sweet Black Angel" live once in the 47 years since its release. That was during the first of two Fort Worth, Texas shows played on June 24, 1972. The song was adapted for stage with chugging "Midnight Rambler" type guitar, jazz cymbals and horn accents. It took at least a chorus and verse before things gelled.

Alas "Sweet Black Angel" live "stuck out like a sore thumb," Richards said in his 2017 Harper's interview. "It never seemed to really fit into a Stones show."

In 2009, Vermont jam-band Phish performed "Sweet Black Angel" during their Halloween concert covering "Exile" in its entirety. Phish opted for an acoustic, piano-heavy and poppier arrangement. And considerably more Caucasian sounding delivery.

The Rolling Stones weren't the only famous musicians voicing support for Davis during the early '70s. Former Beatle John Lennon and wife Yoko Ono wrote "Angela," an orchestral folk tune from their 1972 studio album "Some Time in New York City," about Davis. Soul singer Aretha Franklin reportedly offered to pay Davis' bond. According to Rolling Stone writer Jamil Smith, "though Franklin put the bail money into escrow, she was out of the country, which prevented her from posting Davis's bond. It was ultimately paid by a progressive white farmer named Rodger MacAfee."

More recently, "Sweet Black Angel" has gone from Stones to stoned. Spain-based cannabis company Samsara Seeds produces a strain called "Sweet Black Angel," which weed information website Wikileaf says was named for that song about Davis. According to Wikileaf, the strain "offers a fruity flavor profile and a pervasive body high that's sure to appeal to cannabis newcomers and veterans alike."

In 2013, Rolling Stone magazine ranked "Sweet Black Angel" at number 57 in their "100 Greatest Rolling Stones Songs" list — ahead of the band's classic ballad "Angie" (which is not about Davis), sublime blues-cover "Love in Vain" and early hit "Heart of Stone," among others. A year earlier, "Exile" landed at number seven on that magazine's "Greatest Albums of All Time." It bested other flagships like Michael Jackson's "Thriller," Bruce Springsteen's "Born to Run," Nirvana's "Nevermind," The Beatles' "Abbey Road" and Miles Davis' "Kind of Blue."

"Exile on Main St" contains at least one more Birmingham-related reference. At one point during the blues-punk song "Rip This Joint," Jagger screams the lyric: "Wham! Bam! Birmingham! Alabam' don't give a damn!"

The band's Alabama connections run deeper. They'd recorded three songs for previous LP "Sticky Fingers" at Sheffield's Muscle Shoals Sound Studios: sex/drugs romp "Brown Sugar," country ballad "Wild Horses" and blues redux "You Gotta Move." The Stones had played concerts at Birmingham's Legion Field in 1965 and Auburn University in 1969. The 1972 tour promoting "Exile" would hit Mobile and Tuscaloosa — and, for later tours, the group returned to Legion Field in 1989 and 1994. Tuscaloosa native and former Allman Brothers Band musician Chuck Leavell has been The Rolling Stones keyboardist since 1982. Chalkville native and Muscle Shoals studio musician Wayne Perkins played eloquent lead-guitar on Stones songs "Hand of Fate," ''Memory Motel," ''Fool To Cry" and "Worried About You."

In 2019, The Rolling Stones are touring once again. The band remains a rattlesnake-potent live act. Angela Davis is still making headlines too. The Birmingham Civil Rights Institute made plans to honor Davis, then rescinded that decision, then rescinded the rescission. Meanwhile, Harvard University acquired Davis' personal archive, including her now-iconic FBI poster. I'm not sure how much press Davis will be doing this year, but the next interview she grants hopefully a journalist will ask her thoughts on "Sweet Black Angel." It would be fascinating to know them. As recent as 18 months ago, Richards hadn't ruled out dusting off "Sweet Black Angel" for a Stones concert, saying of the song, "It's still quite relevant, isn't it? And that's unfortunate. This stuff has stayed with us for too long."