The decline in the export of slaves from East Africa from the end of the eighteenth century onwards had initiated the transformation of the Omani merchant class at Zanzibar into a landed aristocracy. However, the slave relations of production that had developed on Zanzibar, Pemba and the Kenya coast required the continued flow of slaves from the African interior and the marketing of the slave-produced commodities. These activities, therefore, ensured the survival of the commercial sector and of the merchant class in East Africa.

The commercial sector, however, received a greater boost from the end of the eighteenth century with the development of the ivory trade. This was sparked by the collapse of the ivory trade at Mozambique which had created a gap in the supply of ivory to India. A greater and longerterm impetus, though, was given by the steeply rising demand for ivory and other luxuries from the affluent classes in the industrialising countries of the West from the 1820s onwards. What made the ivory sector of Zanzibar's commerce so vibrant and expansive was the fact that, whereas the price of ivory and other luxuries rose steeply in response to the demand in the West, the price of manufactured commodities used in exchange declined throughout the nineteenth century as a result of capitalist competition in the industrial countries. The diverging curves of prices of the exported luxuries and imported manufactured commodities was the dynamic factor in the phenomenal expansion of the commercial hinterland of Zanzibar and the prosperity of the entrepot.

In this expanding trade the Omani and Swahili sections of the merchant class found a new lease of life, especially in coastal trading and in the caravan trade into the interior. However, the ascendant section that initially captured the ivory trade with India and later came to monopolise the trade at the entrepot was of Indian origin. Merchant classes are typically compradorial, accommodating themselves to the prevailing dominant modes of production and classes. Initially these seemed to be the slave mode and the Omani landowning ruling class but, as the century wore on, it became increasingly clear that both were themselves subordinate to the capitalist mode which was becoming a world-wide system.