In March 2005 she performed with Queen at Nelson Mandela's 46664 AIDS benefit concert in South Africa, in August the Georgian-born beauty became a British citizen, and in September she released her second album, "Piece by Piece" in the U.K.
The album did well in Europe, debuting at No. 1 in the UK, Poland and the Netherlands, and at No. 2 in Italy and Germany. It has since earned double platinum status in European sales for more than two million copies sold.
Melua wrote most of the songs on the album, which includes a cover of the 1987 Cure hit "Just Like Heaven" that was heard on the Reese Witherspoon film of the same name.
Now, Melua is setting her sights on success in the United States. She released "Piece by Piece" here on June 6, and headed out on a national tour with opera hunks Il Divo.
Life wasn't always easy for the 21-year-old singer.
According to her official Web site, Melua often had to carry buckets of water up five flights of stairs to the family's flat in Georgia as a small girl. But, Melua found joy in music, beginning with singing lessons when she was 7 or 8.
When she was 9, her family moved to Belfast, where her father had a job as a cardiac surgeon.
"I went to Catholic schools in Northern Ireland, while my younger brother went to a Protestant school," the site quotes her as saying. "I didn't always want to be a singer or songwriter. My ambition when I was thirteen was to be a politician or historian. I honestly thought I'd be able to bring peace to the world. ... If I ruled it! We lived in Belfast for five years."
When she was 13, they moved again, this time to the relative peace of Red Hill, Surrey in England. After gaining very good grades, Katie went to the Brit School (the music performing arts school funded by the British Phonographic Industry).
It was at the Brit school that Melua was spotted by songwriter and producer Mike Bat, and her professional career began.
On her first visit to the The Saturday Early Show she recalled how she met the Queen at one of the first TV shows she did in the UK. Her Majesty came backstage and told Melua she had heard her songs on the radio.
Melua says her style is influenced by the folk music she heard during her early years in Georgia, and the Celtic and pop music she grew up with in Ireland.