The magnitude of the export trade from eastern Africa is difficult to determine, because fewer records were kept than in the Atlantic trade, and other sources often show rather obvious abolitionist bias. Ralph Austen's conservative estimates probably provide minimum base figures for the nineteenth-century Islamic trade. He puts the total slaves exported from the East Coast (Swahili towns) as over 300,000, but about two-thirds of these remained in Africa, that is, they were retained on Zanzibar or went to Zanzibari coastal possessions or Somalia. He estimates that slightly fewer than 500,000 slaves were exported in the Red Sea trade (mostly supplied from the Gulf of Aden). Austen's work does not include figures for the European trade of the eighteenth and early nineteenth centuries.

What happened to Africans who entered the Indian Ocean basin during the late eighteenth and nineteenth centuries? They either lived and died as slaves, or they were manumitted or freed. In any case, in most places it was more possible for them to form stable communities than in the plantation-dominated Atlantic world. The struggle to do so was probably hardest for slaves, and harder for those freed by British patrols than for those manumitted under Islamic law. Initially, as more African slaves arrived with the upswing in the slave trade, social boundaries were clear and probably stronger. Later, among the working poor of Indian Ocean ports, the distinction between slave and free became less clear "as a multi-ethnic urban group of wage workers emerged" (Ewald 2000: 80). What Happened to Africans Slaves in Islamic Societies
In Islamic societies a slave was "simultaneously exchangeable property, a dependent, a person with specified rights, and a member of the Muslim community" (Cooper 1977: 25). Muslims were required to convert the newly enslaved, and Islam granted rights to slaves, including the right to marry and even limited rights to hold property. Rates of manumission were high (manumission was an act of charity for Muslims and economically expedient when the demand for labor was low), and it was not uncommon for manumitted slaves to continue working for their masters in positions of responsibility. The right to marriage helped to keep manumitted slaves in the communities in which they and their families were already integrated. Concubinage was also common. Since the offspring of a master and slave concubine were free and legitimate (if a master admitted paternity), slave-owning families tended to become darker over time. Omanis from the coast - with its greater slave population - were noticeably darker than those from inland families.

In southern Arabia where slavery was pervasive, Africans became domestic servants, agricultural workers, sailors (even commanders of ships), trusted retainers, and soldiers. The founder of the Busaidi dynasty of Oman (mid-eighteenth century) had a thousand soldiers from eastern Africa in his army and a special guard of a hundred Nubians (Cooper 1977: 35). Just as fascinating is the Omani recruitment of mercenaries from Baluchistan (Afghanistan), so that Zanzibari forces on the East Coast, even after the separation of Oman and Zanzibar, included Baluchis. In Oman's patrimonial system, the value of service rendered by a slave or freedman was appreciated by the ruler, his rivals, and wealthy merchants. For Omanis, to own slaves was a way to display wealth (Cooper 1977). What Happened to Africans Slaves in India
Much less is known about African slaves and the African diaspora in India. The Portuguese imported slaves to Diu and to Goa, mostly from Mozambique. Often their slaves were domestic servants, but there are sources suggesting that Africans also served as soldiers and sailors (Alpers 1997). Elsewhere in India it is still possible to trace communities of African descent, whose members are called Sidis (sometimes Habshis), for example the Sidis of Hyderabad. Sidi (pronounced see-dee) comes from seyyid, the same Arabic word that the Busaidi rulers of Oman used as a royal title! This term acknowledges role of Arab Muslim traders in conveying Africans (converts to Islam) to India. The ancestors of Sidis include men who had crewed or commanded dhows; they were usually slaves, but some might have been freedmen. In nineteenth-century sources, Sidi is a more general label for any person entering the Indian Ocean world from Zanzibar or other East Coast ports (Ewald 2000: 83). There are identifiable Sidi communities in Gujarat, Maharashtra (around Bombay), and Hyderabad.

When European commerce and warfare in the eighteenth century tightened the maritime labor market, Europeans (the British in particular) stepped up their efforts to recruit African and Asian sailors. These "lascars" (Indian Ocean sailors) crewed ships sailing in Atlantic as well as Indian Ocean waters. Among the lascars were individuals that sources identify as Sidis. By the early nineteenth century, the British were employing so many "lascars" that Parliament enacted legislation requiring them to return to their home ports. These "Asian Articles" reflected growing fears over the consequences of racial mixing in among port populations (Ewald 2000: 75).

In general, slaves exported to Indian Ocean ports provided labor in the harbor, construction, and food-processing sectors - and these sectors were growing in the nineteenth century (Ewald 2000). After the Suez Canal opened, for example, the number of Muslim pilgrims traveling to Mecca rose rapidly, and more labor was required to house and feed them. At Jidda, slaves worked alongside free Arabs in these sectors. In Aden, where the British had abolished slavery, many Yemeni workers were recruited, but freeborn Somalis and Sidis also loaded coal onto ships and operated small boats in the harbor. British territories (especially Aden), Consulates, and ships were havens for slaves seeking freedom. Those who were successful usually joined the local labor force or became sailors because it was too difficult for them to return to Africa (where slave raiding had disrupted their home communities). At least two thousand Africans were working in Bombay in the 1860s (more than half were sailors). Some of these workers were freedmen who had migrated from Aden, but others had been rescued by British anti-slavery patrols and sent to Bombay. These "Bombay Africans" learned skilled trades in mission schools; eventually a few of the better-educated returned to East Africa as missionaries. The Lasting Influence of African Culture
What is most fascinating about the African diaspora in the Indian Ocean is the African cultural dimension that has survived despite the strength of assimilative processes in these communities. African culture has survived especially in the aesthetic domains of music and dance. European visitors to Oman in the nineteenth century described dances, singing, and instruments that are obviously African, sometimes including a word or two that confirm this inference (Alpers 1997). Alpers draws on his own research and a few specialized studies to show the "naturalization" of eastern African musical styles and dance genres into Omani, Somali, and Indian (Sidi) popular cultural as traditional forms. Through its sponsorship of ethnomusicological research, the Omani government is starting to recognize the legacy of slavery in Oman. Thus, when scholars examine the western Indian Ocean as a cultural corridor, they see connections between people of eastern African origin and host communities that are more positive than the consequences of nineteenth century commercial relationships.