By the time of the first recorded contact with the Europeans, the Kingdom of Kongo was a highly developed state at the center of an extensive trading network. Apart from natural resources and ivory, the country manufactured and traded copperware, ferrous metal goods, raffia cloth, and pottery. The Kongo people spoke in the Kikongo language. The eastern regions, especially that part known as the Seven Kingdoms of Kongo dia Nlaza (or in Kikongo Mumbwadi or "the Seven"), were particularly famous for the production of cloth.