De Ishtar was born in Adelaide in 1953. She was awarded an MA by Macquarie University, and an MPhil by the University of Sydney. In 1982 she travelled to the United Kingdom to join the Greenham Common Women's Peace Camp, where she spent much of her time at Green Gate. Whilst there she started the Women Working for a Nuclear Free and Independent Pacific (WWNFIP) movement in the UK. She stated that the movement was born as the result of a party held at the protest camp to "celebrate the strength of our Indigenous Pacific sisters". The organisation campaigned to raise awareness amongst British peace activists about the issues facing colonized Pacific countries.
