Julia Gillard, 51, challenged her former boss Kevin Rudd in June 2010 to the leadership of the ruling Australian Labor Party in June 2010.
The ballot took place after Rudd lost the backing of key factional leaders. Gillard won the vote and became prime minster.
The Welsh-born lawyer was portrayed by some political commentators in 2010 as a warmer, more voter-friendly politician than the bookish Rudd.
The flame-haired politician, who became Australia's first female prime minister, has proven to be one of the government's best public performers in parliament.
However, she has faired less well in the media since and has come under attack for controversial changes in policy.
Commentators point to her 2010 election pledge that there would be no carbon tax under a government she led.
Labor won minority government with three independent Members of Parliament and one Australian Greens MP, she agreed to a fixed-price carbon tax and a floating-price Emissions Trading Scheme.
The opposition Liberal-National coalition accused Gillard of breaking an election promise, but the Clean Energy Bill was passed in 2011.
It promted a leading radio broadcaster, Alan Jones, to label her "Ju-liar". The label stuck and it is a popular moniker among her critics.
The unpopularity of the policy shift led to the re-emergence of Kevin Rudd, who was then foreign minister, as a leadership challenger.
Gillard called a leadership ballot, known as a spill in Australia, in February 2012 after Rudd announced his intention to seek the leadership. Gillard won that spill by a vote of 71 to 31.
Misogyny definition change
Her popularity increased in October 2012 when she made an impassioned attack on the opposition leader's views on women in parliament.
"If he wants to know what misogyny looks like in modern Australia, he doesn’t need a motion in the House of Representatives; he needs a mirror," Gillard said of Tony Abbott.
That speech in parliament prompted the most authoritative dictionary in Australia to update its definition of the word 'misogyny' to imply "entrenched prejudice against women" as well as, or instead of, pathological hatred of them.
Born on September 29, 1961 in Barry, Wales, Gillard's family migrated to Australia in 1966.
She studied arts and law in Adelaide and became the president of the Australian Union of Students in 1983.
Gillard forged a career in industrial relations law, becoming a partner with Slater and Gordon in 1990, before edging into politics as chief of staff to then Victoria state's opposition leader John Brumby.
After initially being rejected by the party for a parliamentary seat, she went to parliament in 1998 after winning the safe seat of Lalor in Melbourne.
Gillard has no children but has a partner, Tim Matheson, dubbed in the media as the "First Bloke".
Comments from a conservative politician in 2007 that she was unqualified to run the country because she was "deliberately barren" prompted a national outcry.
Modern Australian women understood they had choices and such comments were irrelevant, she said at the time.
She discussed the issue of children during an interview in 2008. She said she was "full of admiration for women who can mix it together, working and having kids, but I'm not sure I could have".
"There's something in me that's focused and single-minded and if I was going to do that [have a family], I'm not sure I could have done this [have a political career]," she told the ABC.
Gillard became the country's most powerful female when she became deputy leader to Rudd in 2007 but insisted she was not in politics to become the "first woman to do something".
"I became involved in order to pursue what I thought was a vision of a better country," she said at the time.