modern Zambia is deduced from oral records, archaeology, and written records mostly from non-Africans. Bantu origins The Bantu people originally lived in West/Central Africa around what is today Cameroon/Nigeria. Around 4000 to 3000 years ago, they began a millennia-long expansion into much of the continent. This event has been called the Bantu Expansion, which was one of the largest human migrations in history. The Bantu are believed to have been the first to have brought iron working technology into large parts of Africa. The Bantu Expansion happened primarily through two routes: one was western via the Congo Basin and the other was eastern via the African Great Lakes. First Bantu settlement The first Bantu people to arrive in Zambia came through the eastern route via the African Great Lakes. They arrived around the 1st millennium AD. Among them were the Tonga people (also called Ba-Tonga, "Ba-" meaning "men") and the Ba-Ila and other related groups who settled around Southern Zambia near Zimbabwe. According to Ba-Tonga oral records, they are believed to have come from the east near the "big sea". They were later joined by the Ba-Tumbuka who settled around Eastern Zambia and Malawi. These first Bantu people lived in large villages. They never had an organised unit under a chief or headman and worked as a community and help each other in times of field preparation for their crops. Villages moved around frequently as the soil became exhausted due to using the slash-and-burn technique of planting crops. They also kept large herds of cattle which formed an important part of their societies. The first Bantu communities in Zambia were extremely self-sufficient. Many groups of people who encountered them were very impressed by this self-sufficiency. The early European missionaries that settled in Southern Zambia also noted the extreme independence of these Bantu societies, one of these missionaries noted: "[If] weapons for war, hunting, and domestic purposes are needed, the [Tonga] man goes to the hills and digs until he finds the iron ore. He smelts it and with the iron thus obtained makes axes, hoes, and other useful implements. He burns wood and makes charcoal for his forge. His bellows are made from the skins of animals and the pipes are clay tile, and the anvil and hammers are also pieces of the iron he has obtained. He moulds, welds, shapes, and performs all the work of the ordinary blacksmith."