Sinéad O'Connor and Outlander: Tributes to Irish singer who performed theme song to season 7 of Sam Heughan's time travel drama

Fans and stars of Outlander have been paying tribute to the singer.

Sinéad O'Connor performs on stage at the State Theatre on March 18, 2008, in Sydney, Australia.

The world of music is in mourning following the news that singing legend Sinéad O'Connor has tragically died at the age of 56.

In a statement released on Wednesday night, the singer’s 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.” The cause of her death has yet to be confirmed.

The star recently lent her vocals to the theme song to Scottish time travel drama Outlander - the first time a new version has been used in seven seasons.

Here's everything you need to know about the song, and how the Irish star came to sing it.

What is the Outlander theme song?

The theme to Outlander is 'The Skye Boat Song', an adaptation of a Gaelic song composed by William Ross in 1782 that was originally entitles 'Cuckoo of the Tree'. The modern version became popular in the late 19th century, with the lyrics changed to tell the story of Bonnie Prince Charlie's journey from Benbecula to the Isle of Skye after being defeated at the Battle of Culloden in 1746. The lyrics were written by Sir Harold Boulton.

How did Sinéad O'Connor come to sing the song for Outlander?

Chiefs at Starz - the studio that makes Outlander - chose the singer to perform a new version of the song for Season 7 of the show.

Showrunner Matthew B. Roberts said: "We are honoured to have Sinéad O’Connor performing ‘The Skye Boat Song.’ Her rendition is, for me, a reminder of all that’s beautiful about 'Outlander'. She is talented beyond measure. Hers is a voice of the ages - one which pierces heart and soul - and embodies the spirit of the show."

What have the Outlander family said about the singer's death?

Caitriona Balfe, who plays Claire Fraser, said in Instagram "I hope you are at peace … and with your baby boy. Thank you for sharing your soul with us and soothing us with your incredible voice beautiful Sinéad."

Outlander's executive producer Maril Davis added: "On behalf of the entire cast and crew of Outlander we are deeply saddened about the news of Sinead’s passing. She was an incredible talent and working with her on this season’s main title song was a true honor. Our thoughts and prayers are with her family during this difficult time."

Showrunner Matthew B. Roberts wrote: "I’m deeply saddened to hear about the passing of Sinead O'Connor. Her distinct voice and brave spirit transformed not only the music scene but also left a deep impact on social issues. She will be remembered for her outstanding contribution to music and her remarkable courage. My deepest condolences to her family, friends, and fans across the globe. May her soul rest in peace and her legacy continue to inspire."

Who sang the song in previous seasons of Outlander?

All six previous seasons of Outlander used the same version of the song by American Emmy Award-winning singer Bear McCreary. It is sung by performer Raya Yarbrough, who  is married to Raya Yarbrough.

What are the lyrics to The Skye Boat Song?

The words to the song are as follows:

Speed, bonnie boat, like a bird on the wing, Onward! the sailors cry; Carry the lad that's born to be king Over the sea to Skye. Verse 1 Loud the winds howl, loud the waves roar, Thunderclaps rend the air; Baffled, our foes stand by the shore, Follow they will not dare. Verse 2 Many's the lad, fought on that day Well the claymore did wield; When the night came, silently lay Dead on Culloden's field. Verse 3 Though the waves leap, soft shall ye sleep, Ocean's a royal bed. Rocked in the deep, Flora will keep Watch by your weary head. Verse 4 Burned are their homes, exile and death Scatter the loyal men; Yet ere the sword cool in the sheath Charlie will come again.