A ruined hill fortress in this nation was the capital of the Kingdom of Ma ⋅ pun ⋅ gub ⋅ we, which was a predecessor to Great Zimbabwe, and it is the only nation to have voluntarily destroyed its nuclear arsenal. The states of Natal, Cape Colony, the Orange Free State, and Transvaal were united by the British to form this modern commonwealth. This country where the Soweto massacre took place sentenced one of its future presidents to imprisonment 
A ruined hill fortress in this nation was the capital of the Kingdom of Ma ⋅ pun ⋅ gub ⋅ we, which was a predecessor to Great Zimbabwe, and it is the only nation to have voluntarily destroyed its nuclear arsenal. The states of Natal, Cape Colony, the Orange Free State, and Transvaal were united by the British to form this modern commonwealth. This country where the Soweto massacre took place sentenced one of its future presidents to imprisonment on Robben Island, and it was led by F. W. de Klerk and Nelson Mandela. For 10 points, name this African nation whose largest city is Johannesburg.
A ruined hill fortress in this nation was the capital of the Kingdom of Ma ⋅ pun ⋅ gub ⋅
Republic of South Africa