Ancient[edit] Tanzania is one of the oldest continuously inhabited areas on Earth. The Olduvai Gorge, in the Ngorongoro Conservation Area, a UNESCO World Heritage Site, features a collection with remnants of tools that document the development and use of transitional technology. The indigenous populations of eastern Africa are thought to be the linguistically isolated Hadza and Sandawe hunter-gatherers of Tanzania.[16]: page 17  The first wave of migration was by Southern Cushitic speakers who moved south from Ethiopia and Somalia into Tanzania. They are ancestral to the Iraqw, Gorowa, and Burunge.[16]: page 17  Based on linguistic evidence, there may also have been two movements into Tanzania of Eastern Cushitic people at about 4,000 and 2,000 years ago, originating from north of Lake Turkana.[16]: pages 17–18  Archaeological evidence supports the conclusion that Southern Nilotes, including the Datoog, moved south from the present-day South Sudan / Ethiopia border region into central northern Tanzania between 2,900 and 2,400 years ago.[16]: page 18  These movements took place at approximately the same time as the settlement of the iron-making Mashariki (Eastern) Bantu from West Africa in the Lake Victoria and Lake Tanganyika areas, as part of the centuries-long Bantu expansion. The Bantu peoples brought with them the west African planting tradition and the primary staple of yams. They subsequently migrated out of these regions across the rest of Tanzania between 2,300 and 1,700 years ago.[16][17] Eastern Nilotic peoples, including the Maasai, represent a more recent migration from present-day South Sudan within the past 500 to 1,500 years.[16][36] The people of Tanzania have been associated with the production of iron and steel. The Pare people were the main producers of sought-after iron for peoples who occupied the mountain regions of north-eastern Tanzania.[37] The Haya people on the western shores of Lake Victoria invented a type of high-heat blast furnace, which allowed them to forge carbon steel at temperatures exceeding 1,820 °C (3,310 °F) more than 1,500 years ago.[38] Travelers and merchants from the Persian Gulf and India have visited the east African coast since early in the first millennium AD.[39] Islam was practiced by some on the Swahili Coast as early as the eighth or ninth century AD.[40] Medieval[edit] Bantu-speakers built farming and trade villages along the Tanzanian coast from the outset of the first millennium. Archaeological finds at Fukuchani, on the north-west coast of Zanzibar, indicate a settled agricultural and fishing community from the 6th century CE at the latest. The considerable amount of daub found indicates timber buildings, and shell beads, bead grinders, and iron slag have been found at the site. There is evidence for limited engagement in long-distance trade: a small amount of imported pottery has been found, less than 1% of total pottery finds, mostly from the Gulf and dated to the 5th to 8th century. The similarity to contemporary sites such as Mkokotoni and Dar es Salaam indicate a unified group of communities that developed into the first centre of coastal maritime culture. The coastal towns appear to have been engaged in Indian Ocean and inland African trade at this early period. Trade rapidly increased in importance and quantity beginning in the mid-8th century and by the close of the 10th century Zanzibar was one of the central Swahili trading towns.[41] Growth in Egyptian and Persian shipping from the Red Sea and the Persian Gulf revitalised Indian Ocean trade, particularly after the Fatimid Caliphate relocated to Fustat (Cairo). Swahili agriculturalists built increasingly dense settlements to tap into trade, these forming the earliest Swahili city-states. The Venda-Shona Kingdoms of Mapungubwe and Zimbabwe in South Africa and Zimbabwe, respectively, became a major producer of gold around this same period. Economic, social, and religious power was increasingly vested in Kilwa, Tanzania's major medieval city-state. Kilwa controlled a number of smaller ports stretching down to modern-day Mozambique. Sofala became the major gold emporium and Kilwa grew rich off the trade, lying at the southern end of the Indian Ocean Monsoons. Kilwa's major rivals lay to the north, in modern-day Kenya, namely Mombasa and Malindi. Kilwa remained the major power in East Africa until the arrival of the Portuguese at the end of the 15th century.[42] Colonial[edit] Main articles: German East Africa and Tanganyika Territory A 1572 depiction of the city of Kilwa, a UNESCO World Heritage Site Claiming the coastal strip, Omani Sultan Said bin Sultan moved his capital to Zanzibar City in 1840. During this time, Zanzibar became the centre for the east African slave trade.[43] Between 65 and 90 per cent of the Swahili population of Zanzibar was enslaved.[44][clarification needed] One of the most infamous slave traders on the East African coast was Tippu Tip, who was the grandson of an enslaved African. The Nyamwezi slave traders operated under the leadership of Msiri and Mirambo.[45] According to Timothy Insoll, "Figures record the exporting of 718,000 slaves from the Swahili coast during the 19th century, and the retention of 769,000 on the coast."[46] In the 1890s, slavery was abolished.[47] Battle during the Maji Maji Rebellion against German colonial rule in 1905 In 1863, the Holy Ghost Mission established an early reception center and depot at Zanzibar. In 1877, responding to appeals of Henry Stanley following his trans-Africa expedition, and permission being given to Stanley by King Mutessa I of Buganda, the Church Missionary Society sent missionaries Edward Baxter and Henry Cole to establish inland missions.[48][49][50] In 1885, Germany conquered the regions that are now Tanzania (minus Zanzibar) and incorporated them into German East Africa (GEA).[51] The Maji Maji Rebellion, between 1905 and 1907, was an uprising of several African tribes in German East Africa against the colonial authorities, in particular because of forced labour and deportation of certain tribes. It was the subject of a bloody repression, which combined with famine caused 300,000 deaths among the population, out of a Tanganyikan population of about four million.[52] The Supreme Council of the 1919 Paris Peace Conference awarded all of GEA to Britain on 7 May 1919, over the strenuous objections of Belgium.[53]: 240  The British colonial secretary, Alfred Milner, and Belgium's minister plenipotentiary to the conference, Pierre Orts [fr], then negotiated the Anglo-Belgian agreement of 30 May 1919[54]: 618–9  where Britain ceded the north-western GEA provinces of Ruanda and Urundi to Belgium.[53]: 246  The conference's Commission on Mandates ratified this agreement on 16 July 1919.[53]: 246–7  The Supreme Council accepted the agreement on 7 August 1919.[54]: 612–3  On 12 July 1919, the Commission on Mandates agreed that the small Kionga Triangle south of the Rovuma River would be given to Portuguese Mozambique,[53]: 243  w