<P> The Benin Empire, which occupied present - day Nigeria between the fourteenth and nineteenth centuries, was very rich in sculptures of diverse materials, such as iron, bronze, wood, ivory, and terra cotta . The Oba's palace in Benin, the site of production for the royal ancestral altars, also was the backdrop for an elaborate court ceremonial life in which the Oba, his warriors, chiefs and titleholders, priests, members of the palace societies and their constituent guilds, foreign merchants and mercenaries, and numerous retainers and attendants all took part . The palace, a vast sprawling agglomeration of buildings and courtyards, was the setting for hundreds of rectangular brass plaques whose relief images portray the persons and events that animated the court . </P> <P> Bronze and ivory objects had a variety of functions in the ritual and courtly life of the Kingdom of Benin . They were used principally to decorate the royal palace, which contained many bronze works . They were hung on the pillars of the palace by nails punched directly through them . As a courtly art, their principal objective was to glorify the Oba--the divine king--and the history of his imperial power or to honor the queen mother . Art in the Kingdom of Benin took many forms, of which bronze and brass reliefs and the heads of kings and queen mothers are the best known . Bronze receptacles, bells, ornaments, jewelry, and ritual objects also possessed aesthetic qualities and originality, demonstrating the skills of their makers, although they are often eclipsed by figurative works in bronze and ivory carvings . </P> <P> In tropical Africa of the continent's center, the technique of lost - wax casting was developed early, as the works from Benin show . When a king died, his successor would order that a bronze head be made of his predecessor . Approximately 170 of these sculptures exist, and the oldest date from the twelfth century . The Oba, or king, monopolized the materials that were most difficult to obtain, such as gold, elephant tusks, and bronze . These kings made possible the creation of the splendid Benin bronzes; thus, the royal courts contributed substantially to the development of sub-Saharan art . In 1939, heads very similar to those of the Benin Empire were discovered in Ife, the holy city of the Yoruba, which dated to the fourteenth and fifteenth centuries . This discovery supported an earlier tradition holding that it was artists from Ife who had taught Benin the techniques of bronze metalworking . Recognition of the antiquity of the technology in Benin advanced when these sculptures were dated definitively to that era . </P> <P> Few examples of African art had been collected by Europeans in the eighteenth century . Only at the beginning of the nineteenth century, when colonization and missionary activity began, did larger numbers of African works begin to be taken to Europe, where they were described as simple curiosities of "pagan" cults . This attitude changed after the Benin Expedition of 1897 . </P>

How did the mastery of the lost-wax casting technique transfer from ife to benin
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