Sinéad O’Connor has died in London at the age of 56. The cause of death hasn't been revealed.

The talented but troubled Irish artist released 10 studio albums, while her indelible rendition of Prince’s “Nothing Compares 2 U” was named the #1 world single in 1990 by the Bible.

She was signed to Ensign Records in the U.K. by Nigel Grainge, Sir Lucian’s brother and Elliot Grainge's uncle. Her first four LPs were released by Ensign in Britain and Chrysalis in the States.

Her second, 1990’s I Do Not Want What I Haven't Got, went to #1 in the U.S., U.K. and other territories, triggered by the worldwide chart-topping success of “Nothing Compares 2 U.” She won the Grammy in 1991 for Best Alternative Music performance for the record.

Beyond the pop and rock of her two most famous albums, 1987’s The Lion & The Cobra and I Do Not Want What I Haven’t Got, O’Connor recorded a broad spectrum of styles—jazz standards, traditional Irish tunes, reggae and covers of writers such as Curtis Mayfield and John Grant—but none connected with the public the way her first two records did.

O’Connor was a lightning rod for controversy. In 1990, she threatened to cancel a performance in New Jersey if The Star-Spangled Banner was played at the venue; Frank Sinatra was among those who criticized her stance. She bailed on an appearance on Saturday Night Live in protest of the host, Andrew Dice Clay, and his material.

Two years later, the criticism grew louder after O’Connor tore up a photo of Pope John Paul II after performing Bob Marley’s “War” a cappella. “Fight the real enemy,” she said, referring to sexual abuse in the Catholic Church. Two weeks later, she was booed at a Bob Dylan tribute concert at Madison Square Garden, leaving the stage before finishing her performance of “War.”

“I’m not sorry I did it. It was brilliant,” O’Connor said of the photo-ripping incident in an interview with the New York Times in 2021. “But it was very traumatizing. It was open season on treating me like a crazy bitch.”

Her life and career were made turbulent by her decades-long struggle with mental illness.

O’Connor said her mother physically abused her in her youth and that, as an adult, she had been diagnosed with a bipolar disorder. In 2012, she said she was suffering from post-traumatic stress disorder stemming from child abuse.

She’d moved from her hometown of Dublin to London earlier this year and said on Facebook that she was finishing an album to be released next year, with a world tour to follow. Her 10th album, the final release of her lifetime, was 2014’s I'm Not Bossy, I'm the Boss. O'Connor's memoir, Rememberings, was published in June 2021.

Sinéad was an extraordinary talent. She could move us with a candour and a passion with which so many people connected. The path she chose was always difficult and uncompromising but at every turn she would show her spirit and her courage. I feel lucky to have had the chance to… pic.twitter.com/nSwZ4fTU64
— Peter Gabriel (@itspetergabriel) July 27, 2023

Sinead …
You bared your soul…
Shared your brilliance
Through exquisite artistry
Your incredible voice..
Fierce and fragile
Lioness and lamb
Sweet singing bird
Keenly tuned
Trembling..
Tip-toeing along the high wire
Or stamping the ground
Raw
Wounded
Fearless … pic.twitter.com/QyCX2TT1fn
— Annie Lennox (@AnnieLennox) July 27, 2023

Sad to hear of the passing of sister Shuhada Sadaqat, also known as Sinéad O'Connor. She was a tender soul, may God, Most Merciful, grant her everlasting peace. Inna lillahi wa inna ilayhi rajioon - Verily we belong to God, and verily to Him do we return. 2:156 pic.twitter.com/arcZ3fPWK9
— Yusuf / Cat Stevens (@YusufCatStevens) July 26, 2023

I think what's so hateful about that Guardian Sinead obit is the way it frames her whole life in negatives - "she lacked the obsessive drive needed…never had another hit…inability to edit her pronouncements...constitutionally unable to compromise…" Talk about removing agencyðŸ˜¡
— Tracey Thorn (@tracey_thorn) July 27, 2023

for all us street kids, for all us wildlings, when sinead got huge, it felt like one of us made it. It was incredible. im not trying to compare myself or anyone else to sinead, she is one of a kind, but thats what it felt like to me. like she was one of us. she was like billie…
— Flea (@flea333) July 27, 2023