Tanzania is one of the oldest known inhabited areas on Earth; fossil remains of humans and pre-human hominids have been found dating back over two million years. More recently, Tanzania is believed to have been populated by hunter-gatherer communities, probably Cushitic and Khoisan speaking people. About 2,000 years ago, Bantu-speaking people began to arrive from western Africa in a series of migrations. Later, Nilotic pastoralists arrived, and continued to immigrate into the area through to the 18th century.
The people of Tanzania are associated with the production of steel. The Haya people of East Africa invented a type of high-heat blast furnace which allowed them to forge carbon steel at 1,802 °C (3,276 °F) nearly 2,000 years ago. The Shana clan in the Pare tribe also produced iron.
One of Tanzania's most important archeological sites is Engaruka in the Great Rift Valley which includes an irrigation and cultivation system.
Travellers and merchants from the Persian Gulf and western India have visited the East African coast since early in the first millennium AD. Islam was practised on the Swahili Coast as early as the eighth or ninth century AD.
Claiming the coastal strip, Omani Sultan Seyyid Said moved his capital to Zanzibar City in 1840. During this time, Zanzibar became the centre for the Arab slave trade. Between 65% to 90% of the population of Arab-Swahili Zanzibar was enslaved. One of the most famous slave traders on the East African coast was Tippu Tip, who was himself the grandson of an enslaved African. The Nyamwezi slave traders operated under the leadership of Msiri and Mirambo. 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."
In the late 19th century, Imperial Germany conquered the regions that are now Tanzania (minus Zanzibar), Rwanda, and Burundi, and incorporated them into
