1975), and the Zimbabwe African People's Union (led by Joshua Nkomo from its founding in the early 1960s). History Pre-colonial era Archaeological records date human settlement of present-day Zimbabwe to at least 500,000 years ago. The earliest known inhabitants were probably San people, who left behind arrowheads and cave paintings. The first Bantu-speaking farmers arrived during the Bantu expansion around 2,000 years ago. Societies speaking proto-Shona languages first emerged in the middle Limpopo River valley in the 9th century before moving on to the Zimbabwean highlands. The Zimbabwean plateau became the centre of subsequent Shona states, beginning around the 10th century. Around the early 10th century, trade developed with Arab merchants on the Indian Ocean coast, helping to develop the Kingdom of Mapungubwe in the 11th century. This was the precursor to the Shona civilisations that dominated the region during the 13th to 15th centuries, evidenced by ruins at Great Zimbabwe, near Masvingo, and by other smaller sites. The main archaeological site used a unique dry stone architecture. The Kingdom of Mapungubwe was the first in a series of trading states which had developed in Zimbabwe by the time the first European explorers arrived from Portugal. These states traded gold, ivory, and copper for cloth and glass. By 1220, the Kingdom of Zimbabwe eclipsed Mapungubwe. This Shona state further refined and expanded upon Mapungubwe's stone architecture, which survives to this day at the ruins of the kingdom's capital of Great Zimbabwe. From 1450 to 1760, the Kingdom of Mutapa ruled much of the area of present-day Zimbabwe, plus parts of central Mozambique. It is known by many names including the Mutapa Empire, also known as Mwene Mutapa or Monomotapa as well as "Munhumutapa", and was renowned for its strategic trade routes with the Arabs and Portugal. The Portuguese sought to monopolise this influence and began a series of wars which left the empire in near collapse in the early 17th century. As a direct response to increased European presence in the interior a new Shona state emerged, known as the Rozwi Empire. Relying on centuries of military, political and religious development, the Rozwi (meaning "destroyers") expelled the Portuguese from the Zimbabwean plateau in 1683 by force of arms. Around 1821 the Zulu general Mzilikazi of the Khumalo clan successfully rebelled against King Shaka and established his own clan, the Ndebele. The Ndebele fought their way northwards into the Transvaal, leaving