This could also be Doris Lessing's Canopus in Argos cycle, and particularly, the second book The Marriages Between Zones Three, Four and Five. The eponymous zones are like planets, like a sequence of metaphoric and geographic territories, and perhaps like separate but bordering planes of existence. Their cultures and systems of governance are different
The main character, Queen Al•Ith is a benevolent resident of matriarchal and utopian Zone 3, who is directed by the Providers—the spiritual rulers of all the zones—to marry Ben Ata, the pugnacious, macho and brutal ruler of Zone 2. Despite their differences, they fall in love and conceive a son, but Al•Ith is then directed by the Providers to return with her son to Zone 3, while Ben Ata is directed to marry Vahshi, the queen of the primitive, barbaric, and nomadic denizens of Zone 5. Al•Ith, deposed by her sister in Zone 3, is exiled to Zone 2, an alienating territory inhabited by enlightened people invisible to Al•Ith. The remainder of the text entails conflicts over, and growing acceptance of the movement of people and ideas between the four zones.