It comes a year after her 17-year-old son Shane died after escaping hospital while on suicide watch.
In a statement shared with Ireland’s national broadcaster RTE and the BBC, her family said: “It is with great sadness that we announce the passing of our beloved Sinéad. Her family and friends are devastated and have requested privacy at this very difficult time.”
Taoiseach Leo Varadkar said O’Connor’s music “was loved around the world and her talent was unmatched and beyond compare.”
Others to pay tribute included Irish comedian Dara O’Briain, author Marian Keyes, the Irish band Aslan, US rapper Ice T, and Tim Burgess, frontman of the rock band The Charlatans.
“Sinead was the true embodiment of a punk spirit,” Burgess wrote on Twitter. ”She did not compromise and that made her life more of a struggle. Hoping that she has found peace.''
O’Connor was born in Dublin in 1966. Around the age of 13, she left her mother and went to live with her father, who had married a new wife in Virginia, USA.
At 15, her shoplifting and truancy led to her being sent to a Magdalene asylum in Dublin for ‘fallen women’ where she lived for 18 months.
Despite later detailing the institution’s “odd” punishments, O’Connor said it was here that a nun spotted her musical talent and bought her a guitar.
Through an advert placed in a local music magazine, O’Connor met Colm Farrelly and formed a band called Ton Ton Macoute, which led to her getting music industry recognition.
She was soon signed to Ensign Records with whom she released her first three studio albums.
She released 10 studio albums over the course of her career, the second of which, 1990’s I Do Not Want What I Haven’t Got sold more than seven million copies.
It was when her video for “Nothing Compares 2 U” first aired on MTV in 1990 that O’Connor was propelled to stardom. Her cover of the half-forgotten Prince track had a particularly poignant resonance for O’Connor, who alleged abuse at the hands of her mother.
“It was an emotional thing for me,” said O’Connor at the time. “My mother was an extremely violent person. Someone who wasn’t well.”
O’Connor’s mother was killed in a car accident in the mid-Eighties.
O’Connor gained a Grammy for her hit, which was recorded with the help of producer Nellee Hooper. She was later invited to Prince’s house in Los Angeles where, according to O’Connor, he berated her for using four-letter words in interviews.
She claimed that she swore at him and that he reacted badly to this. “I ended up having to escape... All I could do was spit. I spat on him quite a bit.”
Throughout her career, O’Connor was known for her outspoken views on politics, religion and women’s rights.
During a 1992 appearance on Saturday Night Live, following an acapella rendition of Bob Marley’s “War”, O’Connor held a photo of Pope John Paul II to the camera and ripped it to pieces in protest of sexual abuse within the Church.
In her 2021 memoir Rememberings, O’Connor said of the incident: “Everyone wants a pop star, see? But I am a protest singer. I just had stuff to get off my chest. I had no desire for fame.”
In 2007, O’Connor told talk show host Oprah Winfrey that she had been diagnosed with bipolar disorder four years previously and that she had struggled with thoughts of suicide in the past. She added that medication had helped her find more balance, but “it’s a work in progress”.
In 2017, O’Connor changed her legal name to Magda Davitt, saying in an interview that she wished to be “free of the patriarchal slave names. Free of the parental curses.”
A year later, she changed her name again to Shuhada Sadaqat after converting to Islam, calling it “the natural conclusion of any intelligent theologian’s journey”; though, continued to perform under the name Sinead O’Connor.
In January 2022, the singer announced the death of her son Shane, who she shared with musician Donal Lunny. “My beautiful son, Nevi’im Nesta Ali Shane O’Connor, the very light of my life, decided to end his earthly struggle today and is now with God,” she wrote at the time.
“May he rest in peace and may no one follow his example. My baby. I love you so much. Please be at peace.”
Following Shane’s death, O’Connor fiercely criticised the Irish health service HSE, the child and family agency Tusla, and the Irish state overall. She later apologised for “lashing out” on social media.
In one of her last tweets, posted on 17 July, O’Connor wrote about her grief: “Been living as undead night creature since. . He was the love of my life, the lamp of my soul. We were one soul in two halves. He was the only person who ever loved me unconditionally. I am lost in the bardo without him.”
Bardo, in Tibetan Buddhism, is a state of existence between death and rebirth.
O’Connor is survived by her three children, Jake Reynolds, Roisin Waters and Yeshua Bonadio.
If you are experiencing feelings of distress, or are struggling to cope, you can speak to the Samaritans, in confidence, on 116 123 (UK and ROI), email email@example.com, or visit the Samaritans website to find details of your nearest branch.
If you are based in the USA, and you or someone you know needs mental health assistance right now, call the National Suicide Prevention Helpline on 1-800-273-TALK (8255). This is a free, confidential crisis hotline that is available to everyone 24 hours a day, seven days a week.
If you are in another country, you can go to www.befrienders.org to find a helpline near you.