Early Arab settlers
The 7th century ad saw the rise of Islam in Arabia. At the same time wars in this area, and subsequent unrest in Persia, caused a small number of people from these regions to escape to the east African coast, where they settled permanently, bringing the new Islamic religion with them.
There are several accounts of emigrations from Arabia to east Africa. (The history of this period is largely based on stories handed down by word of mouth through generations, which are difficult to separate from myth and legend.) One story tells of two Arab chiefs from Oman who arrived in east Africa with their families around the end of the 7th century, and settled on the island of Pate, near Lamu. Another story tells of an emigration from Shiraz, in Persia, some time between the 8th and 10th centuries. The Sultan of Shiraz and his six sons migrated with their followers in seven boats. One of the sons stopped at Pemba, while others settled in Mombasa and Kilwa. The 9th-century Arab tale of Sinbad the Sailor, one of the stories in The Arabian Nights, was most probably inspired by accounts of journeys by Arab sailors to east Africa and southeast Asia.
The rise of the Swahili
During the second half of the first millennium, the coastal bantu people developed a language and culture (in fact, a whole civilisation) which became known as swahili. This name came from the arabic word sahil meaning 'coast'. Their language, kiswahili, although bantu in origin, contained many arabic words. It also included some persian words, mainly nautical terms. There was some intermarriage, and the swahili adopted many arab customs and traditions, including the islamic religion. On unguja (zanzibar island), shirazi settlers are believed to have married into the family of the island's swahili king. Several centuries later, the mwinyi mkuu ('the great lord'), the traditional ruler of unguja, continued to claim descent from a shirazi prince.
By the 7th century, the Swahili people were trading regularly with Arab and Persian merchants. In the same way, Swahili dhows (traditional ships based on an Arab design) also became involved in the trade and sailed regularly to and from the Persian Gulf, carrying gold, ivory, rhino-horn, leopard skins, tortoiseshell, and ambergris from whales. African slaves were also carried to the Persian Gulf, probably to work in the marshlands of Mesopotamia.
Over the following centuries the trade between Africa and Arabia increased, as did trading links between east Africa and Asia. Ivory was exported to India, and later China, while Indian cloth and Chinese porcelain and silk were imported to Arabia and Zanzibar. At around this time, Indonesian sailors from Java and Sumatra are thought to have reached east Africa and Madagascar, possibly introducing coconuts and bananas.
From this period (7th to 10th centuries) archaeologists have discovered a very distinctive kind of local pottery, known as Tana Tradition, which looks the same at sites along the whole east African coast, from northern Kenya to southern Tanzania, and out to the Comoros Islands. The similarity of this pottery over such a large area shows how closely linked the people of the coast were, and also shows – for the first time – a sense of commonality and shared experience. Imported ceramics, called Sassian Islamic, from the Persian Gulf have also been discovered.
Archaeological, linguistic and historical research conducted since the early 1980s has also led to a shift in the way that the early history of the coast is interpreted, rejecting some of the ideas put forward by scholars working during the 1950s, 1960s and 1970s. In essence, this research suggests that at its core – its foundation – Swahili culture and history are an African phenomenon. Until recently, archaeologists had proposed that the large towns of the east African coast (such as Kilwa, Lamu, Mombasa and Unguja Ukuu) had been built by Persian or Arab settlers, and the local Bantu people had then intermarried and 'Africanised' the Arabs, thus resulting in the Swahili people. But, through extensive excavations at many of these towns, it is now known that they were founded by people from the interior of Africa and, instead of simply starting as grand towns, were actually built up slowly over time by these same people.
Unquestionably, the links to the Indian Ocean trade were some of the most important for these towns, but there is little evidence of large-scale migrations from Arabia or Persia to the coast of east Africa until the middle of the second millennium.