Wangari Maathai, the first African woman recipient of the Nobel Peace Prize, died after a long struggle with cancer, the environmental organization she founded said. She was 71.
One of Kenya's most recognizable women, Maathai won the Nobel in 2004 for combining environmentalism and social activism. She was the founder of the Green Belt Movement, where over 30 years she mobilized poor women to plant 30 million trees.
Edward Wageni, that group's deputy executive director, said Maathai died in a Nairobi hospital late Sunday. Maathai was in and out of the hospital since the beginning of the year, he said.
In recognizing Maathai, the Nobel committee said that she had stood up to a former oppressive regime in Kenya and that her "unique forms of action have contributed to drawing attention to political oppression."
Maathai said during her 2004 acceptance speech that the inspiration for her life work came from her childhood experiences in rural Kenya, where she witnessed forests being cleared and replaced by commercial plantations, which destroyed biodiversity and the capacity of forests to conserve water.
Although the Green Belt Movement's tree planting campaign did not initially address the issues of peace and democracy, Maathai said it become clear over time that responsible governance of the environment was not possible without democracy.
"Therefore, the tree became a symbol for the democratic struggle in Kenya. Citizens were mobilized to challenge widespread abuses of power, corruption and environmental mismanagement," Maathai said.
The Green Belt Movement, which was founded in 1977, said on its web site that Maathai's death was a great loss to those who "admired her determination to make the world a more peaceful, healthier and better place."
Maathai is survived her three children. Funeral arrangements were to be announced soon, the Green Belt Movement said.
