City Hall said that Margolles, who is from Mexico, “works closely with this marginalised community that sometimes is unable to access social care”.
“The ‘life masks’ will be arranged round the plinth in the form of a Tzompantli, a skull rack from Mesoamerican civilisations (an area covering Central Mexico to northern Costa Rica),” the statement added.
Margolles is known for portraying social causes and the consequences of death in her work and her Trafalgar Square piece will go on display in 2024.
Kambalu’s work, titled Antelope, depicts a 1914 photograph of Baptist preacher John Chilembwe and European missionary John Chorley.
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Chilembwe led an uprising against colonial rule and the sculpture shows the preacher wearing a hat, defying a colonial rule which banned Africans from wearing headwear in front of white people.
City Hall said Kambalu’s piece, which goes on display next year, reveals “the hidden narratives of under-represented peoples in the history of the British Empire in Africa and beyond”.
The upcoming works of Margolles and Kambalu become part of a rolling commission of public artwork on the plinth, which are chosen by the Fourth Plinth Commissioning Group after almost 17,500 members of the public voted for their favourite designs.
Paloma Varga Weisz, Ibrahim Mahama, Goshka Macuga and Nicole Eisenman had also been shortlisted.
Mayor of London Sadiq Khan said: “Our international shortlist showed again that the Fourth Plinth is one of the most important art commissions in the world, and I’d like to congratulate Samson Kambalu and Teresa Margolles as the next artists to have their work displayed.
“They will be shining a spotlight on important issues that our society continues to face, and I know they will spark debate and interest at home and abroad.”
The most recent commission, which is on display until September 2022, was Heather Phillipson’s sculpture The End, which portrayed a whirl of cream topped with parasites.
Previously, British sculptor Antony Gormley created One & Other, in which people – including a man who posed naked – took it in turns to spend an hour on the plinth.