Much of Swahili literature, including proverbs and canonical works like Utendi wa Mwana Kupona, denigrate watumwa (slaves) as if blacks were not forcibly captured, raped, castrated, and uprooted from their cultures. The casualness with which slavery is treated, even by progressive poets like Muyaka, is the biggest scandal in Swahili letters.
(Evan Mwangi, in his essay We Need a Slave Rebellion in Literary Studies of Swahili, that reviews two books, The Story of Swahili and The Cultural Politics of Translation: East Africa in Global Contexts)