Apartheid
Apartheid is similar in some ways to American Segregation because both were legally imposed rules of segregating Black communities from European communities. This was extremely bitter for the native African communities who had already been dealing with European civilization on their continent for many centuries. For Rosa, the imagery of this historical setting is of the utmost value; she gives her life to be a justice warrior in one of the most intense seasons of political and racial strife in African history.
Peace and violence
Sometimes, the imagery is peaceful and proactive. Other times, the novel is merely reacting to extreme outbursts of public rage. Throughout the novel, the threat of violence looms in the streets. To be a white person in the wrong part of town could be a life sentence. But, because of the stubborn injustice of the South African government, the schism in the community only worsens until finally, by the end of the novel, the imagery of peace is over, and the imagery of violence dominates. For Rosa, this means a subjection to torture and murder, probably.
Riots and chaos
The novel shows the birth and rise of riots in South Africa. These riots are absolute rejections of South African community and civilization. We see that from the targets of riotous violence—it is white servants of the Black community who are martyred by angry mobs. Why kill the people who provide social benefits? The answer is that the solutions offered by the government are merely a distraction from the real political corruption and injustice that the government has no interest in fixing. This is painful and confusing imagery on all sides.
Tyranny
Tyranny is when a government abandons its ethical obligation to the people and follows an esoteric agenda instead. This is obviously most likely with a monarch because only one person has to behave selfishly, but in South Africa, the Europeans all hold positions of power while the native population just has to deal with whatever paltry provisions the government will provide them. This novel's imagery of tyranny is racial imbalance of power and oligarchy. The native African population is disenfranchised from power.