The Luba Empire was founded in 1585, in the Upemba depression by King Kongolo. His nephew and successor, Kalala ilunga, rapidly expanded the kingdom to encompass all the territories on the upper left bank of the Lualaba River. At its peak, about one million people living in several tribes, were paying tribute to the Luba King. At the end of the 19th century, with the advance of the Ovimbundu people from Angola and the raids of the East African Muslim slavers, the empire weakened and in fact, collapsed when the Belgian colonies took control. With the assistance of a court of notables, called Bamfumus, the king, known as the Mulopwe, reinged over his subjects through clan Kings called Balopwe. These clan Kings could symbolically become the Mulopwe’s son which created client states through the empire. A secret society, Bambudye, kept the memory of the Luba Empire alive and permeated throughout Luba territory, bonding the diverse populations together. Luba empire economy was complex –it was based on a tribute system and the redistribution of resources from agriculture, fishing, hunting and mining. The production of salt and iron was under the king ‘control.