Greta Thunberg is a Swedish environmental activist. She became famous after protesting outside the Swedish parliament in 2018, when she was 15, with a sign that read “Skolstrejk för Klimatet” (School Strike for Climate). By December 2018, more than 20,000 students had supported the cause. A year later, she received the first of three Nobel Peace Prize nominations for climate activism. Thunberg has received support from climate activists, scientists and public figures, such as the broadcaster and naturalist Sir David Attenborough, who told her she had achieved things many others had failed to do.