Wangari Maathai was the first woman in Central and East Africa to earn a Ph.D., but she learned the ways of the world by planting trees. In 1977, she founded the Green Belt Movement to teach peasant women livelihoods while reforesting urban areas. That wholesome pursuit was seen as a threat by Kenya’s land-grabbing politicians, and in 2001, Maathai spent International Women’s Day in jail, where she often found herself.
But having found organic links between environmentalism, poverty reduction and democratic rights, she a year later won a Parliament seat with 98% of the vote. The Nobel Peace Prize followed in 2004. By the time of her death in 2011, Maathai had taken on palm-oil plantations in Southeast Asia, and her movement, with branches in 30 countries, had planted 50 million trees. —Karl Vick
This article is part of 100 Women of the Year, TIME’s list of the most influential women of the past century.
Here’s the full list of honorees:
THE 100 WOMEN OF THE YEAR:
1920 The Suffragists 1921 Emmy Noether 1922 Xiang Jingyu 1923 Bessie Smith 1924 Coco Chanel 1925 Margaret Sanger 1926 Aimee Semple McPherson 1927 Queen Soraya Tarzi 1928 Anna May Wong 1929 Virginia Woolf 1930 Martha Graham 1931 Maria Montessori 1932 Babe Didrikson 1933 Frances Perkins 1934 Mary McLeod Bethune 1935 Amelia Earhart 1936 Wallis Simpson 1937 Soong Mei-ling 1938 Frida Kahlo 1939 Billie Holiday 1940 Dorothea Lange 1941 Jane Fawcett and the Codebreakers 1942 The Resisters 1943 Virginia Hall 1944 Recy Taylor 1945 Chien-Shiung Wu 1946 Eva Perón 1947 Amrit Kaur 1948 Eleanor Roosevelt 1949 Simone de Beauvoir 1950 Margaret Chase Smith 1951 Lucille Ball 1952 Queen Elizabeth II 1953 Rosalind Franklin 1954 Marilyn Monroe 1955 The Bus Riders 1956 Golda Meir 1957 Irna Phillips 1958 China Machado 1959 Grace Hopper 1960 The Mirabal Sisters 1961 Rita Moreno 1962 Jacqueline Kennedy 1963 Rachel Carson 1964 Barbara Gittings 1965 Dolores Huerta 1966 Stephanie Kwolek 1967 Zenzile Miriam Makeba 1968 Aretha Franklin 1969 Marsha P. Johnson 1970 Gloria Steinem 1971 Angela Davis 1972 Patsy Takemoto Mink 1973 Jane Roe 1974 Lindy Boggs 1975 American Women 1976 Indira Gandhi 1977 Judith Heumann 1978 Lesley Brown 1979 Tu Youyou 1980 Anna Walentynowicz 1981 Nawal El Saadawi 1982 Margaret Thatcher 1983 Françoise Barré-Sinoussi 1984 bell hooks 1985 Wilma Mankiller 1986 Corazon Aquino 1987 Diana, Princess of Wales 1988 Florence Griffith Joyner 1989 Madonna 1990 Aung San Suu Kyi 1991 Anita Hill 1992 Sinead O’Connor 1993 Toni Morrison 1994 Joycelyn Elders 1995 Sadako Ogata 1996 Ruth Bader Ginsburg 1997 Ellen DeGeneres 1998 J.K. Rowling 1999 Madeleine Albright 2000 Sandra Day O’Connor 2001 Wangari Maathai 2002 The Whistleblowers 2003 Serena Williams 2004 Oprah Winfrey 2005 Melinda Gates 2006 Ellen Johnson Sirleaf 2007 Lilly Ledbetter 2008 Michelle Obama 2009 Malala Yousafzai 2010 Nancy Pelosi 2011 Tawakkol Karman 2012 Pussy Riot 2013 Patrisse Cullors, Alicia Garza and Opal Tometi 2014 Beyoncé Knowles-Carter 2015 Angela Merkel 2016 Hillary Rodham Clinton 2017 The Silence Breakers 2018 Maria Ressa 2019 Greta Thunberg
This article originally appeared on Time Magazine