Mandela had been arrested multiple times for illegally leaving the country and treason.
In 1963, "Rivonia", the secret meeting place of Mandela and other anti-apartheid activists, was discovered.
Eventually, the activists, including Mandela, were tried for sabotage and treason. Mandela spent 27 years in prison, 18 of those years on Robben Island.
"I have cherished the ideal of a democratic and free society in which all persons live together in harmony and with equal opportunities. It is an ideal which I hope to live for and to achieve. But if needs be, it is an ideal for which I am prepared to die"
Mandela admitted to some of the charges against him while defending the ANC's actions and denouncing the injustices of apartheid.
During his time in prison, Mandela did not give up the fight. He continued his teaching and his message spread all around the world.
Nelson Mandela sacrificed a lot, but many South Africans can thank him for helping to end apartheid.