Ramaphosa has now been ordered to launch an investigation into objections by some members of the Zulu royal house that the correct processes were not followed in selecting kaZwelithini as the rightful heir to the throne.
KaZwelithini was chosen as the new king last year after the death of his father, King Goodwill Zwelithini.
He was recognized by Ramaphosa as the new king and handed a recognition certificate, but some of his siblings have challenged the process and insisted that he is not the rightful heir to the throne and that due processes were not followed in choosing him.
In a judgment delivered by Judge Norman Davis in the Pretoria High Court on Monday, Ramaphosa was criticized for not launching an investigation after he became aware that there was a dispute in the royal house regarding the selection of the heir to the throne.
According to South African law, which recognizes and affords some rights and responsibilities to traditional leadership, Ramaphosa was supposed to launch an investigation as soon as he was aware of objections against the recognition of the new king.
“It is declared that the recognition by the first respondent of the second respondent as Isilo of the Zulu nation was unlawful and invalid and the recognition decision is hereby set aside,” reads the judgment.
The judge noted that his ruling was not meant to determine whether the king was the rightful heir, but whether the correct processes had been followed.
The president has now been ordered to appoint a committee to investigate the disputes.
The Zulu royal house is estimated to control about 30% of the land in South Africa's eastern KwaZulu-Natal province through the Ingonyama Trust.
It also receives an annual budget of more than $4 million from the provincial government for the upkeep of the royal households and cultural activities.
According to the latest national census, isiZulu is the most spoken language in South Africa with 24.4% of households speaking it.
The royal house has not yet responded to the judgment.
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