An exhibition now on in Johannesburg commemorates the campaign of defiance against apartheid during the 1950s. This selection of photos is by Jurgen Schadeberg.

Thousands took to the street to protest against unjust laws, and to break them.

Jurgen Schadeberg was born in Germany but made his name in South Africa, documenting developments from the 1950s until now.

Nelson Mandela was an ANC youth leader in 1951 when he urged his organisation to take up the defiance campaign.

Laws restricted free movement and hampered racial mixing - here the police confront Indian women who marched to a black township.

The leaders of the defiance campaign were tried in the Johannesburg Magistrates' Court in August 1952.

Protests continued outside the court, where the campaign leaders eventually received suspended jail sentences.

At the time, Nelson Mandela shared a legal practice with fellow ANC leader Oliver Tambo.

Covering the 1956 treason trial, Schadeberg was himself arrested while trying to help fellow photographer Peter Mugubane, who was being beaten by the police.