A man paces a 50-meter stage doing breathing exercises. Crew members chatter while putting together final touches to the set, as a pianist rehearses.

Acclaimed South African artist William Kentridge's play "The Head & The Load" is almost ready for its much-awaited African debut.

"Being able to show it at home feels very important," Kentridge told AFP of the show, which centers on African porters who, at the call of their colonial masters, hauled arms, cannons and supplies for European forces during World War I.

The production made its international debut in London in 2018 but has never been shown on African soil.

That is set to change on Friday as, after delays caused by coronavirus pandemic, the piece is set to premier at the Joburg Theatre in Johannesburg.

"This piece is about a hidden history, a history that was deliberately hidden," Kentridge, 67, said as the cast took their places for a final dress rehearsal on Thursday night.

About one million African soldiers, porters and laborers are believed to have taken part in the 1914-18 conflict, according to the United Nations cultural agency, UNESCO.

More than 150,000 of them died.

"I think a starting place of the project was an ignorance, and an annoyance at my own self at my own ignorance," the artist said. "I thought I knew the First World War."

'Troubles of the neck'

"The Head & The Load" takes its name from a Ghanaian proverb -- "The head and the load are the troubles of the neck". At the rehearsal, the words are projected in enormous white text onto the stage.

But it takes a brief explanation, and a moment of reflection, to better understand their meaning.

"There's... a physical load that the people are carrying, there's a historical load of how we got here, and there's a psychic load of how does one keep this history in one's head," Kentridge said.

Renowned for his animated films of shape-shifting charcoal drawings, the thickly eye-browed artist described the show as "a very wide drawing... moving in three dimensions", combined with silhouettes, "added text and a great deal of music."

Choreographer Gregory Maqoma said he looked forward to performing for a home audience.

The production aimed at "fulfilling" a void for "those who never made it back home," he said.

Among them was a distant relative of the show's co-composer, 35-year-old, Thuthuka Sibisi, who said one of his ancestors died on board the SS Mendi, a British steamship that sank in the Channel in February 1917.

The vessel was taking more than 600 mostly black South African soldiers to the front in France.

"The role and responsibility here is to... reconsider what we think is history" Sibisi said.

"The Head & The Load" runs at the Joburg Theatre from April 21 to May 6.