NAIROBI, KENYA – 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 Monday. She was 71.

Kenya’s most recognizable woman, 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.

In recognizing Maathai, the Nobel committee said that she had stood up to a former oppressive regime – a reference to former Kenyan President Daniel arap Moi – and that her “unique forms of action have contributed to drawing attention to political oppression.”