Nelson Mandela's activism was profoundly influenced by key historical events such as the Apartheid regime's institutionalized racism, the 1960 Sharpeville Massacre, and the formation of the African National Congress (ANC) Youth League. His 27 years in prison served as a catalyst for his resolve against racial injustice. Mandela's experiences with political imprisonment galvanized both national and international support for the anti-apartheid movement, leading to his eventual leadership in South Africa's transition to democracy and a celebration of human rights.