I've learned (re-learned) at least five important truths that seem to apply nearly worldwide.
1) Mothers, at least in novels, do darn near everything to keep their families going. This is true in Wild Ginger, Children of the Jacaranda Tree, Guardian of the Word, This Earth of Mankind, Bone China, Masks, and others works. Step-mothers, not so much.
2) People of high wealth, at least as described by novelists of unknown wealth, live very insular lives. The high-wealth people in these books have almost no clue about the difficulties of daily living or about the anger and hatred that is often surrounding them. I saw this in Moth Smoke, Born of the Sun, The Unwanted, and Bone China. In these books, the wealthy relied on gates, barbed wire, thugs, guns, and more to preserve their life of "privilege," with parties, imported goods, and very loose sexual mores (read, unpunished rape, widespread adultery, and the perception that access to prostitutes or gigolos is a sign of luxury).
3) People who are subjected to the power of the wealthy in one regime become tyrants--and often corrupt tyrants (one wonders if there is a non-corrupt tyrant?)--when they are handed any level of power by a new regime. This occurred in Wild Ginger, Children of the Jacaranda Tree, Krik? Krak!, Moth Smoke, and Autumn Quail. Note that raising the "underclass" to power has been a strategy both of Communism and fundamentalist Islam, not to mention whatever "Papa Doc" was when he took over Haiti.
5) There is widespread fear of "the other." This usually appears in complexities of how cultures treat people who are somehow different from whatever is determined to be the correct or powerful norm. It takes many forms, though. Nguyen in The Unwanted has lighter hair, eyes, and skin tones and is victimized. He still is "better off" than two girls in Nha trang, his town, whose American father(s) were black. Their own mother kicks them.
Bias against dark skin plays a disturbingly important role in Black Gold of the Sun, especially in Eshun's youth in England, and in Potiki and Born of the Sun. Members of the De Silva clan in Bone China struggle to make a go of it in England, where their many accomplishments and social standing from Sri Lanka count for nothing because of their skin tone.
There are other types of discrimination, too. Sundiata in Guardian of the Word is tormented by his mother's co-wife because of his early lameness (Toko in Potiki is not, though he is also affected by weak legs and a heart defect). In Ghana, Eshun is treated differently because of his Englishness -- he was not Ghana-enough. Rose in The Beggar Maid keenly feels the socio-economic class differences that separate her from others, even as she herself climbs that ladder through education and effort. Even the differences between people of Lithuanian, Polish and Belorussian language and heritage mattered, in the stories of Colours of the Native Country, because of long-standing animosities and centuries of experience fighting over control over resources.
I'll leave for another time my reflections on the gender politics revealed in these and future novels on my list. Be assured, they are as powerful as anything else. I'm in the middle of Nervous Conditions now, a novel about then-Rhodesia (now Zimbabwe). In it one of the characters says,
"This business of womanhood is a heavy burden...How could it not be? Aren't we the ones who bear children?...When there are sacrifices to be made, you are the one who has to make them...And these days it is worse, with the poverty of blackness on one side and the weight of womanhood on the other. Aiwa! What will help you, my child, is to learn to carry your burdens with strength." (p. 16)
While my life has been of ease and privilege in comparison, the advice to learn to carry your burdens with strength--to which I would add learn the strength of your friends--seems sound to me in any culture in any place at any time.