Coast
In pre-colonial times this area supported a coastal civilization as a result of the meeting of local Bantu cultures and the Syrian Muslims who came from the Arabian Gulf area in the 7th century, later joined, according to tradition, by Persians from Shiraz. They produced a language and culture known as Swahili (Arabic for Coast). The language is Bantu in structure and basic vocabulary but with a large Arabic vocabulary as well. Thus it is analogous to English with its Germanic structure and Latin vocabulary. It is at least as old as English with an extensive literature.

The result was a composite culture of great power.

The Swahili lived in trading cities along the coast from Mogadishu in Somalia to Sofala in Mozambique. The most famous of these were Kilwa, Lamu, Pate and Mombasa. Kilwa has been described (by Basil Davidson) as the equivalent of Venice in its trading empire. The trade routes extended across the Indian Ocean to India and to the Gulf. Southward trade passed to the interior of Zimbabwe from where the gold came to Sofala.

A Chinese expedition visited the coast in the 13th century (but beware of theories about further activities - see Speculations).

The Portuguese arrival in the 15th century destroyed the civilization and the trade because they did not understand how it worked. They seized the gold but did not join in the trading system. The Ocean component was destroyed first and then the overland routes to Zimbabwe. The cities fell into decay and the Swahili poets have mourned their emptiness, as described in the (Swahili) Chronicles of Kilwa. The decline was accelerated by the arrival in 1587 of the Zimba, a people who seem to have come from Sena in Mozambique and who had the same effect on the coast as Genghis Khan in Eurasia or Shaka the Zulu in southern Africa (see Psychopaths).

The Portuguese were driven out from the northern area - Mombasa to Mtwara - by the Omani Arabs from their new base on Zanzibar but the coastal civilization never recovered its former brilliance and prosperity, as the Portuguese still occupied Sofala and controlled the trade to Zimbabwe. The coast later came under the control of British, German, Portuguese and Italian colonial empires until independence. Swahili remains the common language of the coast and in a simplified form is used in the interior as far west as eastern Zaire. Its literary qualities continue.

The area was known as Azania in the ancient Greek "Periplus of the Erythraean Sea" by the geographer Ptolemy. By the Arabs and Chinese it was known as the Land of the Zanj - hence Zanzibar. Political co-operation has been lacking since soon after independence but may be growing again now - see East African Community.

Western area
In the west of this area is the Interlacustrine area, now shared between Uganda, Tanzania, Rwanda, Burundi and Zaire.

This Interlacustrine area is characterised by a caste system of aristocrats, once thought to be descended from non-Bantu cattle herders, probably speaking Nilotic languages now typical of the southern Sudan. Various names: Tutsi and Hima are the most common names for the upper castes; Hutu and Iru for the peasant Bantu speakers. Some of the customs of these kingdoms may possibly be traced back to ancient Egypt, perhaps via Meroe in Sudan. It was comprised of the kingdoms of Buganda, Bunyore, Toro, Ankole, Rwanda, Burundi and Buhaya (Tanzania), and some others. The origin of these kingdoms is now disputed among historians and a re-assessment is taking place. Only in the 19th century did the Arabs from the coast start travelling to the lakeside kingdoms.

The southern part of the area was affected by the Mfecane started by Shaka the Zulu, whose activity brought warlike refugees from southern Africa into southern Tanzania.

Central area (eastern Rift)
The interior of Kenya and Tanzania, along the Rift Valley was the home of cattle herding peoples who spoke Nilotic languages (once classified as Nilo-Hamitic) with their origin in southern Sudan.

Ethiopia itself was the home of a Semitic speaking population, which became influenced first by Judaism, then by Christianity. Influences from here spread southward.