Leona Louise Lewis (born 3 April 1985) is a British singer, songwriter and animal welfare campaigner. She was born and raised in the Islington, London, where she attended the BRIT School for Performing Arts and Technology. Lewis achieved national recognition when she won the third series of The X Factor in 2006, winning a £1 million recording contract with Simon Cowell's record label, Syco Music. Her winner's single, a cover of Kelly Clarkson's "A Moment Like This", peaked at number one for four weeks on the UK Singles Chart and it broke a world record for having 50,000 digital downloads within 30 minutes. In February 2007, Lewis signed a five-album contract in the United States with Clive Davis's record label, J Records.

Lewis's success continued with the release of her debut album, Spirit, in 2007; it went 10x platinum in the United Kingdom, while the lead single, "Bleeding Love", spent seven weeks at number one. She achieved international recognition with the album in 2008, when she became the first British female solo artist to top the US Billboard 200 album chart in more than 20 years. Spirit has sold more than eight million copies worldwide, and "Bleeding Love" peaked at number one in over 30 countries, becoming the best-selling single of 2008. As a result, she was proclaimed 'Top New Artist' by Billboard in 2008. Under the guidance of Cowell and Davis, Lewis released her second UK number-one album Echo and recorded the theme song for the film Avatar in 2009, while embarking on her first UK arena tour, The Labyrinth, in 2010.

In 2011, Lewis released the non-album single "Collide", a collaboration with Swedish DJ Avicii, and her first extended play, Hurt: The EP. Her third album, Glassheart, was released in 2012. It marked a new creative direction for Lewis, drawing inspiration from dubstep and electronic music. However, it failed to match the commercial performance of her two previous albums, peaking at number three on the UK Albums Chart and becoming her first to not be certified platinum. Lewis began to record material for her first Christmas album during her Glassheart Tour, which took place in mid 2013. Christmas, with Love was released later that year. Its lead single, "One More Sleep", peaked at number three in the UK. With this chart entry, Lewis became the first British female solo artist to achieve eight top 5 singles, surpassing Olivia Newton-John's record of seven.

With a career starting in 2006, Lewis is the second best-selling act to have emerged from The X Factor franchise, having sold 20 million records worldwide.Lewis has won one Bambi Award, an MTV Video Music Award and three World Music Awards. She is also a seven-time Brit Award and three-time Grammy Award nominee. In 2014, Lewis made her film debut in the supporting role of Elena in the romantic comedy musical, Walking on Sunshine. Amongst her many awards, in 2015 she also received the Women's Entrepreneurship Day Music Pioneer Award at the United Nations. In July 2016, Lewis will make her Broadway debut as Grizabella in the revival of Andrew Lloyd Webber's musical Cats.

On 12 February 2015, Lewis uploaded a video to YouTube which showed the singer performing a new song called "Fire" in a studio.On 16 February, she uploaded a video to her Instagram account which showed her recording vocals in the studio for new tracks.On 14 April 2015 she performed an intimate showcase in London, where she revealed "Fire Under My Feet" to be the lead single from her fifth studio album. She also showcased four other songs, "I Am", "I Got You", "Ladders" and "Thank You".Shortly after, the album title was confirmed to be I Am. "Fire Under My Feet" premiered on BBC Radio 2 on 11 May 2015.Lewis later revealed that I Am would be released on 11 September 2015, in the UK. On 13 June 2015, Leona Lewis premiered another song from the album, called "Essence of Me," via Graham Norton on BBC Radio 2. In July 2015 "I Am" and "Thunder" were released as second and third single from the album respectively. "Thunder" serves as the lead single from the album in the US.

On 11 September 2015, following the album's release, Lewis announced her third live tour with an initial leg of fourteen UK dates. On the tour Lewis will visit major cities including Birmingham, London, Cardiff and Glasgow. On 12 December the singer performed at the The X Factor UK final alongside fellow X Factor UK winner Ben Haenow, on the show the duet consisted of Lewis's song "Run" and Haenow's "Slamming Doors". That same month Lewis performed a cover of "Girl Crush" with Adam Lambert. In May 2016 the performance earned the pair a CMT Music Award nomination.On 18 March 2016, Lewis headlined Cirque du Soleil's One Night for One Drop performance in Las Vegas.On 26 May 2016, it was announced that Lewis would make her Broadway debut as Grizabella in the July 2016 revival of Andrew Lloyd Webber's musical Cats.

In June 2016, after two years with the label, it was revealed that Leona and Island Records parted ways due to "something that didn't click." Later that month she released the song "(We All Are) Looking For Home," a charity single created in collaboration with Diane Warren for the Vanderpump Dog Foundation's public service announcement in opposition to the Yulin Dog Meat Festival.