The migration that remade Africa

The dry-stone wall ruins of Great Zimbabwe — an ancient African capital that once presided over a thriving kingdom across much of modern-day Zimbabwe — are one legacy of the Bantu-speaking people who migrated there from western Africa. Between 6,000 and 4,000 years ago, a group known as the Bantu-speaking people began to migrate across Africa, transforming the continent’s cultures, languages and genetic makeup It’s not easy to extract iron from its ore. But the peoples of the ancient city of Great Zimbabwe — the capital of a thriving kingdom in southern Africa between 1000 to 1700 AD — were masters.

At sites near the city’s stone ruins, clusters of iron-smelting furnaces survive today as mounds of rubble. At Mashava, a village 25 miles northwest, fragments bear fingermarks of those who long ago smoothed the structures’ clay interiors. Some of the furnaces were nearly an adult’s arm span in width, with walls thick and strong to contain the heat of more than 2,100 degrees Fahrenheit needed to smelt iron.

Unlike other furnaces that required workers to force air into them with bellows, these were designed to suck air in, then out through a chimney, no human labor required. This would have made it significantly easier to produce the iron, which was fashioned into hoes, axes and arrowheads. At Chigaramboni, a hilly area near Great Zimbabwe, the remains of ancient furnaces showcase Bantu-speaking people’s iron-smelting skills.

Air once entered through blowpipe-like structures called tuyeres (A), while iron ore was smelted into iron in pits at the center of the furnace (D). To archaeometallurgists, the fact that the tuyeres were fused together (B) is an indication that the air wasn’t pumped in manually with bellows, but rather, that the furnaces were designed to draw in air automatically, and out through a chimney. The waste byproducts of smelting —called the slag — shows plant impressions (C), a possible indication that plants were used in the smelting process. .

MTETWA / _AFRICA, THE CRADLE OF HUMAN DIVERSITY_ 2021 Scientists are extremely interested in the peoples who created this and other iron-powered societies across eastern and southern Africa. Research points to an adaptable and innovative group from western Africa as the masterminds. Known as Bantu speakers, these communities began gradually expanding across the continent’s southern half, starting from 6,000 to 4,000 years ago.

In doing so, they introduced a fundamentally new, sedentary way of life — characterized by farming, raising livestock, pottery-making and metalworking — to regions previously dominated by hunter-gatherer communities. This migration transformed not only the region’s history and technology, but also its languages: Today, around 350 million Africans speak one of roughly 500 distinct Bantu tongues, from southern African Zulu to eastern African Swahili. And at least as many Africans — as well as many African Americans and Afro-Latinos — carry Bantu ancestry in their DNA.