People of Heaven by Beverley Harper

'The poacher didn't shoot her. Bullets cost money and a shot might alert the rangers. . . On the third night, after enduring more agony than any man or beast should ever have to face, the rhinoceros took one last shuddering breath, heaved her flanks painfully, and sought refuge in the silky blackness of death.'
In 1945, on a train bound for Zululand, two soldiers meet on the way home to their families, the war in Europe finally over. But in South Africa there are many more battles still to be fought. The seeds of apartheid are being sown in an angry nation, the fate of the Zulu people is as precarious as that of the endangered black rhinoceros, hunted for its horn. The soldiers on the train are already sworn enemies-one is black, the other white.
Their sons, Michael King and Dyson Mpande, share a precious friendship that defies race and colour. But political greed, lust and a great evil between their families will test their friendship beyond imaginable limits.