That the work of the African artist, when dealing with Europeans, was necessarily of an inferior grade must not be assumed to be the rule, however, though it does seem from the evidence that there is more unaccountable archaicness in objects of this character than in any others. Ling Roth, speaking in this same connection, calls attention to the fact that Benin was not discovered by the Portuguese until about 1472, and that by the middle of the sixteenth century (_e.g._, 1550) we have an almost perfect figure of a European, presumably made by a native. "It is inconceivable," he concludes, "that an introduced art could have developed at so rapid a rate that in seventy years, probably less, for this art would hardly have been introduced the first day, such a high pitch of excellence could have been attained by the natives." If the Portuguese theory is untenable, the Arabic or Islamic theory is equally, if not more, unacceptable. In the first place, as has already been pointed out, Arabic or Islamic art shows absolutely nothing in art approaching objects of the Benin type. Furthermore, Islam itself did not appear in Central Africa until the eleventh century, and then only in the northern and western parts of the Sudan. And it was, moreover, not until the fourteenth century that it made itself a real part of the life of the northern country, and not until the eighteenth that its influence spread into Yorubaland. And then its influence was only felt in the back country.[59] Furthermore, according to Frobenius and Ling Roth, respectively, both the Ilifian region and the Benin territory remain until the present-day non-Mohammedan in character. This would seem to indicate Islamic influence in those countries where most of these objects above described were found has been necessarily very slight; yet such a culture as the above objects represent was unquestionably a very integral part of the life of the country and could not possibly have been due to such an influence. Furthermore, if additional evidence were needed to disprove the theory, it might be cited that it is a well-known fact that one of the fundamental tenets of the Islamic faith is the proscription of the representation of the human form in its art in any whatsoever. And since the height of the material side of this culture was reached in this kind of art, it appears doubtful that this culture could have arisen from such a source.