Wangarĩ Muta Maathai was a Kenyan social, environmental, and political activist who founded the Green Belt Movement, an environmental non-governmental organization focused on the planting of trees, environmental conservation, and women's rights. In 2004 she became the first African woman to win the Nobel Peace Prize.

The Green Belt Movement (GBM) is an indigenous grassroots organization in Kenya that empowers women through the planting of trees. It is one of the most effective and well-known grassroots organisations addressing the problem of global deforestation. Professor Wangari Maathai established the organization in 1977 under the auspices of the National Council of Women of Kenya (NCWK). GBM's successes in forest conservation, education, and women's economic empowerment have gained the organisation worldwide acclaim. It is also noted for its advocacy of human rights, democratisation of access to public lands, and environmental justice issues such as the role of women's traditional ecological knowledge in addressing environmental degradation and desertification.