Technology is intrinsically rooted within social contexts. Archaeological approaches which do not take this into account fail to fully understand technology. The social contexts of iron production are examined at lgurwa, an iron-smelting centre within Karagwe, a nineteenth-century African kingdom. At different levels within the society, power was derived from the control and manipulation of technical and ritual knowledge of iron production. Men excluded women, iron-working clans excluded other clans and the king attempted to maintain control over iron workers by the use of ritual religion and symbolism. Control of iron production was essential because of its economic importance but more importantly because of the symbolic dangers associated with smelting which threatened the fertility of the state.