In 2004 Maathai became the first African woman to win the Nobel Peace Prize. The Nobel committee said Maathai was "a source of inspiration for everyone in Africa fighting for sustainable development, democracy and peace".

She gained a BS in Biology and an MS in Biological Studies in American Universities and followed up by gaining a PhD in Anatomy from the University of Nairobi in 1971.

She became a director of the Kenya Red Cross in 1973 (until 1980).

As well as taking on leading academic roles in the University of Nairobi in the late 70s, Maathai importantly established in 1977 an organisation - primarily of women - known as the Green Belt Movement aiming to curtail the devastating effects of deforestation and desertification.

More than 20 million trees have been planted Through the Green Belt Movement. And the campaign has spread across Africa.

She has also become a leading campaigner on social matters including the Jubilee 2000 campaign to cancel African debt.

Professor Maathai was arrested several times for her campaign against deforestation in Africa, and was once beaten unconscious by heavy handed police.

In elections in 2002, she was elected as MP with 98% of the votes as part of an opposition coalition which swept to power after Mr Moi stepped down.

Maathai was appointed Assistant Minister for Environment, Natural Resources and Wildlife in Kenya's ninth parliament.